Cannabis for Epilepsy in Thailand: A Medical Guide

Epilepsy is the condition where medical cannabis — specifically cannabidiol (CBD) — has the strongest scientific evidence of any cannabinoid therapy in modern medicine. Unlike many other conditions where cannabis research remains preliminary, the use of CBD for certain forms of epilepsy has been validated through rigorous randomized controlled trials, leading to regulatory approvals in multiple countries.

In Thailand, epilepsy patients can access CBD-dominant cannabis products through the PT 33 medical cannabis prescription system. This guide covers the science behind CBD for seizures, which types of epilepsy respond best, how to access treatment in Thailand, critical drug interactions, and the safety considerations that every epilepsy patient and caregiver must understand.

Important: Epilepsy is a serious neurological condition that can be life-threatening. Cannabis should only be considered as an adjunctive (add-on) therapy alongside existing anti-seizure medications — never as a replacement. Any changes to your seizure management plan should be made under the direct supervision of a neurologist or epilepsy specialist.

Understanding Epilepsy and Seizures

Epilepsy is a neurological disorder characterized by recurrent, unprovoked seizures caused by abnormal electrical activity in the brain. It affects an estimated 50 million people worldwide and is one of the most common neurological conditions globally.

Seizures occur when groups of neurons fire excessively and synchronously, creating an electrical storm in the brain. The type and severity of seizures depend on where in the brain the abnormal activity originates and how far it spreads.

Types of Seizures

Understanding seizure types is important because different types respond differently to cannabis treatment.

Focal (partial) seizures originate in one area of the brain:

• Focal aware seizures — the person remains conscious but may experience unusual sensations, movements, or emotions
• Focal impaired awareness seizures — consciousness is altered; the person may stare blankly or perform repetitive movements
• Focal to bilateral tonic-clonic — begins focally and spreads to involve the entire brain

Generalized seizures involve both hemispheres of the brain from the onset:

• Tonic-clonic (grand mal) — stiffening followed by rhythmic jerking of the body
• Absence seizures — brief staring episodes, most common in children
• Myoclonic seizures — sudden brief jerks of a muscle or group of muscles
• Atonic seizures (drop attacks) — sudden loss of muscle tone, causing falls
• Tonic seizures — sudden stiffening of the body

Treatment-Resistant Epilepsy

Approximately 30% of epilepsy patients do not achieve adequate seizure control with conventional anti-seizure medications. When a patient has tried two or more appropriately chosen and dosed medications without achieving seizure freedom, their condition is classified as drug-resistant or treatment-resistant epilepsy.

This is the population where medical cannabis has shown the most promise — patients who have exhausted conventional options and continue to experience seizures that significantly impair their quality of life.

How CBD Works as an Anticonvulsant

CBD’s anticonvulsant properties are among the best-studied effects of any cannabinoid. Unlike THC, CBD does not bind strongly to CB1 or CB2 cannabinoid receptors. Instead, it works through multiple independent mechanisms that converge to reduce seizure activity.

GPR55 Antagonism

One of CBD’s key anticonvulsant mechanisms involves the GPR55 receptor, sometimes called the “orphan cannabinoid receptor.” GPR55 is widely expressed in the brain, and its activation increases intracellular calcium release and enhances neuronal excitability. CBD acts as an antagonist at GPR55, blocking its activity and thereby reducing the excessive neuronal excitation that drives seizures.

This mechanism is particularly relevant because GPR55 is densely expressed in brain regions involved in seizure generation and propagation.

TRPV1 Modulation

CBD activates and then desensitizes TRPV1 (transient receptor potential vanilloid 1) channels. TRPV1 channels are involved in regulating neuronal excitability and calcium signaling. By desensitizing these channels, CBD reduces the hyperexcitability of neurons, making them less likely to fire in the abnormal patterns that produce seizures.

Sodium Channel Blockade

CBD blocks voltage-gated sodium channels, specifically the Nav1.6 subtype. Many conventional anti-seizure medications (carbamazepine, phenytoin, lamotrigine) also work by blocking sodium channels, so this mechanism places CBD in familiar pharmacological territory. By reducing sodium influx, CBD decreases the rapid firing of neurons that underlies seizure activity.

Calcium Channel Effects

CBD modulates T-type calcium channels, which play a role in generating the rhythmic bursting patterns of neuronal activity seen in certain seizure types, particularly absence seizures. By inhibiting these channels, CBD may help interrupt the thalamocortical circuits involved in generalized seizures.

Adenosine Reuptake Inhibition

CBD inhibits the reuptake of adenosine, an endogenous neuromodulator with strong anticonvulsant and neuroprotective properties. By allowing adenosine to accumulate at synapses, CBD indirectly enhances adenosine signaling, which dampens overall neuronal excitability.

Anti-inflammatory and Neuroprotective Effects

Chronic epilepsy involves neuroinflammation that can both result from and contribute to ongoing seizure activity. CBD’s well-documented anti-inflammatory properties may help break this cycle, reducing the inflammatory mediators that lower seizure thresholds and protecting neurons from excitotoxic damage.

Why Multiple Mechanisms Matter

The fact that CBD works through several independent pathways is clinically significant. It means that CBD may be effective in patients who have not responded to medications targeting a single mechanism (such as sodium channel blockers alone). It also explains why CBD has shown benefit across different seizure types and epilepsy syndromes.

Types of Epilepsy That Respond to CBD

CBD has demonstrated benefit across several epilepsy syndromes, with the strongest evidence in severe childhood-onset forms.

Dravet Syndrome

Dravet syndrome is a rare, severe form of epilepsy that begins in infancy, typically between 5 and 8 months of age. It is caused in most cases by mutations in the SCN1A gene, which codes for a sodium channel subunit. Dravet syndrome is characterized by:

• Frequent, prolonged seizures often triggered by fever
• Multiple seizure types (tonic-clonic, myoclonic, absence, focal)
• Developmental delays and cognitive impairment
• High risk of sudden unexpected death in epilepsy (SUDEP)
• Poor response to most conventional anti-seizure medications

Dravet syndrome is one of the conditions for which CBD (as Epidiolex) has received regulatory approval. Clinical trials demonstrated that CBD, when added to existing medications, reduced convulsive seizure frequency significantly compared to placebo. Many patients experienced a reduction of 30-50% or greater in seizure frequency, and a meaningful proportion achieved periods of seizure freedom.

Lennox-Gastaut Syndrome

Lennox-Gastaut syndrome (LGS) is a severe epilepsy syndrome that typically begins between ages 3 and 5. It is characterized by:

• Multiple seizure types, including tonic, atonic (drop attacks), and atypical absence seizures
• An abnormal EEG pattern (slow spike-and-wave discharges)
• Cognitive impairment and behavioral difficulties
• High resistance to conventional medications

Drop seizures (atonic and tonic seizures) are particularly dangerous in LGS because they cause sudden falls that can result in serious injury. Clinical trials found that CBD significantly reduced the frequency of drop seizures in LGS patients, which represents a meaningful improvement in safety and quality of life.

Tuberous Sclerosis Complex

Tuberous sclerosis complex (TSC) is a genetic disorder that causes benign tumors to grow in the brain and other organs. Epilepsy occurs in approximately 80-90% of TSC patients, often beginning in infancy and frequently proving resistant to conventional treatment.

CBD has been specifically studied in TSC-associated epilepsy, and clinical trial data supported regulatory approval for this indication. Patients with TSC-associated seizures showed significant reductions in seizure frequency with adjunctive CBD therapy.

Treatment-Resistant Focal Epilepsy

Beyond the specific syndromes above, CBD has shown promise in broader populations of patients with treatment-resistant focal (partial) epilepsy. While the evidence is strongest for Dravet, LGS, and TSC, open-label studies and clinical experience suggest that some patients with other forms of refractory epilepsy may also benefit from CBD therapy.

The response is less predictable in these populations, and not all patients will experience meaningful improvement. A supervised trial period with careful seizure tracking is the best way to determine whether CBD is helpful for an individual patient.

Seizure Types That May Not Respond

It is important to set realistic expectations. CBD is not a universal anticonvulsant, and some patients will not experience benefit. In particular:

• Not all seizure types respond equally to CBD
• Patients with certain genetic epilepsies may respond differently based on the underlying cause
• Absence seizures have less evidence supporting CBD use compared to convulsive seizures
• Some patients may experience an initial improvement that diminishes over time

Epidiolex: The Gold Standard

Epidiolex (cannabidiol oral solution) represents a landmark in cannabis medicine — the first plant-derived cannabis medication to receive regulatory approval from the United States Food and Drug Administration (FDA).

What Epidiolex Is

Epidiolex is a purified, pharmaceutical-grade CBD oral solution manufactured by GW Pharmaceuticals (now part of Jazz Pharmaceuticals). It contains 100 mg/mL of CBD in a sesame oil base with no significant THC content. Unlike dispensary CBD products, Epidiolex undergoes the same rigorous manufacturing, quality control, and testing as any conventional pharmaceutical.

Regulatory Approvals

• FDA-approved (United States, 2018) for Dravet syndrome, Lennox-Gastaut syndrome, and later expanded to include tuberous sclerosis complex in patients aged 1 year and older
• EMA-approved (European Medicines Agency, 2019) for adjunctive therapy of seizures associated with Dravet syndrome and Lennox-Gastaut syndrome
• Additional regulatory approvals have followed in multiple countries

Why Epidiolex Matters

The approval of Epidiolex is significant for several reasons:

1. It validated CBD as a legitimate anticonvulsant through the gold-standard process of randomized, double-blind, placebo-controlled clinical trials
2. It established dosing guidelines based on rigorous pharmacokinetic studies
3. It documented the safety profile including side effects, drug interactions, and monitoring requirements
4. It provided a benchmark against which other CBD products can be measured

Epidiolex in Thailand

Epidiolex is not widely available in Thailand through standard channels. However, the clinical evidence generated by Epidiolex trials directly informs how Thai practitioners use CBD for epilepsy. The dosing protocols, drug interaction data, and safety monitoring guidelines derived from Epidiolex research are applied by knowledgeable practitioners when prescribing locally available CBD products.

The key difference is that locally available CBD products in Thailand may not have the same pharmaceutical-grade consistency as Epidiolex. This makes third-party testing, certificate of analysis documentation, and reputable sourcing especially important for epilepsy patients who need precise, reliable dosing.

Clinical Trial Evidence

The evidence supporting CBD for epilepsy comes from some of the most rigorous research in cannabis medicine.

Randomized Controlled Trials

Multiple large-scale, randomized, double-blind, placebo-controlled trials have evaluated CBD for epilepsy. The key findings across these studies include:

Efficacy outcomes:

• CBD at doses of 10-20 mg/kg/day reduced convulsive seizure frequency by approximately 30-50% compared to baseline in patients with Dravet syndrome
• Drop seizure frequency was reduced significantly in Lennox-Gastaut syndrome patients
• A meaningful percentage of patients (ranging from 2-5% in different trials) achieved complete seizure freedom during the treatment period
• Benefits were sustained in long-term open-label extension studies, with many patients maintaining seizure reduction over years of treatment

Response rates:

• Approximately 40-50% of patients met the threshold for “responder” status (50% or greater reduction in target seizure frequency)
• Even patients who did not meet this threshold often experienced clinically meaningful improvements
• Caregivers reported improvements in overall condition and quality of life

Open-Label and Expanded Access Studies

Large expanded access programs, which enrolled patients with a wider range of epilepsy types, found similar patterns of benefit. These real-world data are important because they include patients who might not meet the strict inclusion criteria of controlled trials, making the findings more generalizable to clinical practice.

Long-Term Data

Long-term follow-up data spanning several years suggest that:

• Seizure reduction is generally maintained over time, though some patients experience fluctuations
• Some patients show continued improvement beyond the initial treatment period
• Side effects tend to be most prominent during the dose-titration phase and may diminish with time
• The safety profile remains acceptable with appropriate monitoring

CBD vs THC for Epilepsy

The distinction between CBD and THC is critically important for epilepsy patients. These two cannabinoids have very different — and in some respects opposite — effects on seizure activity.

CBD: The Primary Anticonvulsant

CBD is the cannabinoid of choice for epilepsy treatment. Its advantages include:

• Proven anticonvulsant properties validated in multiple clinical trials
• No psychoactive effects — crucial for patients who need to maintain cognitive function, especially children
• Multiple mechanisms of action targeting different aspects of seizure generation
• Regulatory approval for specific epilepsy syndromes
• Acceptable safety profile with known and manageable side effects
• No abuse potential — CBD is not addictive and is not a controlled substance in most jurisdictions

THC: A More Complicated Picture

THC’s role in epilepsy is controversial and nuanced:

Potential benefits:

• Some preclinical evidence suggests THC may have anticonvulsant properties at low doses
• THC may help with seizure-related symptoms such as pain, sleep disturbance, and appetite loss
• The “entourage effect” theory suggests that small amounts of THC alongside CBD may enhance therapeutic benefit, though this is not definitively proven for epilepsy

Significant risks:

• THC has a biphasic effect on seizures: low doses may be anticonvulsant, but higher doses can be proconvulsant (increasing seizure risk)
• THC’s psychoactive effects are particularly problematic for pediatric patients and those with cognitive impairment
• THC can impair memory, attention, and executive function — all of which may already be affected by epilepsy
• THC may lower seizure threshold in some patients, potentially triggering seizures
• THC is a controlled substance requiring a PT 33 prescription in Thailand

The Practical Recommendation

For epilepsy treatment, the recommendation is clear:

1. CBD-dominant products are first-line — use products with high CBD content and minimal THC
2. Avoid THC-dominant products for seizure management
3. If using products with trace THC, ensure the THC content is minimal and consistent
4. Some practitioners may consider balanced or slightly THC-containing products for specific secondary symptoms (sleep, pain), but only after seizure control is well established
5. Never use THC as a standalone seizure treatment

Thai Clinical Experience with Epilepsy

How Thai Practitioners Approach Epilepsy

Thailand’s dual system of Western medicine and Traditional Thai Medicine creates a unique landscape for epilepsy treatment with cannabis. In practice, epilepsy patients accessing cannabis in Thailand typically follow a pathway that involves:

• Neurologist oversight for the underlying epilepsy diagnosis, conventional medication management, and monitoring
• Cannabis practitioner involvement for PT 33 prescription, product selection, and dose titration
• Coordination between providers — particularly important given the drug interactions between CBD and anti-seizure medications

Thai practitioners with experience in cannabis for epilepsy report that:

• CBD-dominant oils are the most commonly prescribed cannabis product for seizure patients
• Many patients present after failing multiple conventional medications
• Family involvement (especially for pediatric patients and those with intellectual disabilities) is essential for proper administration and monitoring
• Seizure diaries kept by patients or caregivers are a crucial tool for evaluating treatment response
• Conservative dosing and slow titration are emphasized, given the drug interaction profile

Available Products

The cannabis products used for epilepsy in Thailand include:

• Government Pharmaceutical Organization (GPO) CBD-dominant oil — available at government hospitals and some licensed clinics, offering a more affordable option
• Private-label CBD oils — available at licensed dispensaries, often with detailed certificates of analysis
• Imported CBD products — some clinics carry products manufactured to international standards

For epilepsy specifically, the quality and consistency of the CBD product matters more than for almost any other condition. Seizure patients need reliable, consistent dosing, and variations in CBD content between batches can affect seizure control.

Pediatric Considerations

Epilepsy frequently affects children, and some of the most severe forms (Dravet syndrome, Lennox-Gastaut syndrome) begin in early childhood. Pediatric use of CBD for epilepsy requires special consideration.

Extra Caution Required

Children are not simply small adults when it comes to cannabis medicine. Key differences include:

• Developing brain — the pediatric brain is still maturing, and the long-term effects of cannabinoid exposure on brain development are not fully understood
• Different pharmacokinetics — children metabolize drugs differently than adults, which affects dosing and drug interactions
• Communication challenges — young children and those with developmental delays may not be able to report side effects effectively
• Dosing precision — weight-based dosing must be carefully calculated and administered

Specialist Involvement Is Essential

Pediatric epilepsy patients considering cannabis should have:

• A pediatric neurologist or epileptologist managing the overall seizure treatment plan
• A cannabis practitioner experienced in pediatric cases for prescribing and dose guidance
• Clear communication between all providers regarding the treatment plan
• Regular monitoring including follow-up appointments, blood work, and seizure tracking

In Thailand’s PT 33 system, practitioners have discretion in prescribing for qualifying conditions including epilepsy, but responsible practitioners will insist on specialist involvement for pediatric cases.

What Parents Should Know

• CBD for epilepsy in children is an adjunctive therapy — it is added to existing medications, not used instead of them
• Improvement, if it occurs, typically develops gradually over weeks to months
• Not every child will respond, and expectations should be realistic
• Side effects must be closely monitored and reported promptly
• The child’s anti-seizure medication doses may need adjustment as CBD is added, due to drug interactions
• Keep a detailed seizure diary and share it at every appointment

PT 33 Access Process

Epilepsy patients in Thailand can access CBD-dominant cannabis products through the PT 33 system. For a complete overview of the prescription process, see our PT 33 Prescription Guide.

Steps for Epilepsy Patients

1. Gather your medical records — Bring your epilepsy diagnosis, EEG reports, brain imaging results, a list of all current medications with dosages, and documentation of medications previously tried
2. Find a qualified practitioner — Look for a clinic with experience in neurological conditions. Our clinic directory can help you locate licensed practitioners
3. Initial consultation — The practitioner will review your history, discuss treatment goals, and determine whether cannabis is appropriate for your case
4. PT 33 prescription issued — If approved, you will receive a PT 33 form that is valid for 30 days
5. Product dispensed — CBD-dominant oil is the standard product for epilepsy patients
6. Follow-up scheduled — Typically within 2-4 weeks to assess initial response and adjust dosing

Costs

• Consultation fee: 300-1,500 THB depending on the facility
• GPO CBD oil: 200-800 THB (government hospital pricing)
• Private-label CBD products: 800-3,500 THB depending on concentration and volume
• PT 33 renewal: Required every 30 days; some clinics include renewal in the follow-up consultation fee
• Blood tests (liver function, drug levels): Additional costs if required by your neurologist

Government hospitals generally offer the most affordable pathway to treatment.

What to Bring to Your Appointment

• Thai ID or passport
• Complete medication list with dosages and timing
• Seizure diary covering at least the previous 1-2 months
• Any relevant medical reports (EEG, MRI, blood work)
• A caregiver or family member who can help communicate your seizure history
• Previous neurologist or epileptologist correspondence

Product Types for Epilepsy

CBD Oils (Primary Treatment)

CBD oil administered sublingually (under the tongue) is the standard product for epilepsy treatment. Key characteristics:

• Precise dosing — measured in milligrams using calibrated droppers or syringes
• Consistent absorption — sublingual administration provides relatively reliable bioavailability
• Gradual onset — effects begin within 15-45 minutes, peak at 1-3 hours
• Duration — therapeutic effects last approximately 4-8 hours
• Twice-daily dosing — most patients take CBD oil morning and evening

When selecting a CBD oil for epilepsy, prioritize:

• Products with a certificate of analysis from a third-party laboratory
• Consistent CBD concentration across batches
• Minimal THC content (ideally below 0.2% or as low as possible)
• A reputable manufacturer with transparent sourcing

CBD Capsules

Pre-dosed capsules may be convenient for some patients, particularly:

• Adults who prefer the simplicity of a fixed dose
• Patients who dislike the taste of CBD oil
• Situations where precise milliliter measurement is difficult

However, capsules have a slower onset and less predictable absorption compared to sublingual oil, which is why oil remains the preferred format for epilepsy.

Products to Avoid for Epilepsy

• THC-dominant products — risk of proconvulsant effects
• Inhaled cannabis (flower, vaporizers) — dosing is too imprecise for seizure management, and rapid THC delivery is not appropriate
• Edibles with variable dosing — inconsistent cannabinoid content makes reliable seizure management difficult
• Unregulated products without testing — potency and purity cannot be verified

Dosage Guidance

Dosing CBD for epilepsy follows a specific protocol based on body weight. The guidelines below reflect the dosing strategies established in clinical trials and used by experienced practitioners.

Starting and Titrating

Initial dose:

• Begin at 2.5 mg/kg/day of CBD, divided into two doses (morning and evening)
• For a 70 kg adult, this would be approximately 87.5 mg CBD twice daily (175 mg total daily)
• For a 20 kg child, this would be approximately 25 mg CBD twice daily (50 mg total daily)

Titration schedule:

Week	Daily CBD Dose	Notes
Week 1-2	2.5 mg/kg/day	Starting dose, split into morning and evening
Week 3-4	5 mg/kg/day	Increase if tolerated and seizures persist
Week 5-6	7.5 mg/kg/day	Further increase if needed
Week 7+	Up to 10 mg/kg/day	Maximum dose used in most clinical settings

Some clinical trials used doses up to 20 mg/kg/day, but higher doses are associated with more side effects, particularly when combined with other medications. The target is the lowest effective dose.

Important Dosing Principles

• Increase gradually — never jump to a high dose. The slow titration allows for monitoring of side effects and drug interactions
• Maintain consistency — take CBD at the same times each day
• Do not skip doses — consistent blood levels are important for seizure control
• Do not adjust without guidance — dose changes should be directed by your practitioner
• Weight-based dosing — always calculate dose based on the patient’s current weight, particularly important for growing children

When to Expect Results

• Some patients notice seizure reduction within the first 2 weeks
• For others, meaningful improvement may take 4-8 weeks at an adequate dose
• If no improvement is seen after reaching 10 mg/kg/day and maintaining that dose for at least 4 weeks, CBD may not be effective for that individual
• Do not continue increasing the dose indefinitely — there is a ceiling beyond which more CBD does not produce better seizure control and side effects increase

Critical Drug Interactions with Anti-Epileptic Drugs

This is one of the most important sections in this guide. CBD has significant pharmacokinetic interactions with many commonly prescribed anti-seizure medications. These interactions are well-documented and must be managed by your medical team.

CBD primarily inhibits the liver enzymes CYP3A4 and CYP2C19, which are responsible for metabolizing many anti-epileptic drugs (AEDs). When CBD inhibits these enzymes, blood levels of other medications can rise, potentially increasing both their therapeutic effects and their side effects.

Clobazam (Frisium, Onfi)

This is the most clinically significant interaction. CBD inhibits CYP2C19, the primary enzyme responsible for metabolizing clobazam. The result:

• Blood levels of norclobazam (the active metabolite of clobazam) can increase by 2-5 times
• This increase causes excessive sedation and drowsiness — the most common side effect reported in clinical trials of CBD for epilepsy
• Dose reduction of clobazam is almost always necessary when CBD is added, typically by 25-50%
• Paradoxically, some of the seizure reduction seen with CBD may be partly attributable to increased clobazam levels
• Monitor closely for sedation, lethargy, and respiratory depression

Valproate (Valproic Acid, Depakote, Epilim)

CBD combined with valproate carries a specific safety concern:

• Both CBD and valproate are metabolized in the liver and both can cause hepatotoxicity (liver damage)
• The combination increases the risk of elevated liver enzymes (transaminases)
• In clinical trials, liver enzyme elevations were more common in patients taking CBD plus valproate compared to CBD without valproate
• Regular liver function tests are mandatory — typically at baseline, 1 month, 3 months, and every 6 months thereafter
• If liver enzymes rise above 3 times the upper limit of normal, CBD dose reduction or discontinuation should be considered
• Symptoms of liver problems include jaundice (yellowing of skin or eyes), dark urine, nausea, vomiting, abdominal pain, and unusual fatigue

Topiramate (Topamax)

• CBD may increase topiramate blood levels through CYP enzyme inhibition
• Monitor for increased side effects of topiramate including cognitive dulling, word-finding difficulties, tingling in extremities, decreased appetite, and kidney stones
• Dose adjustments may be needed

Phenobarbital

• CBD can increase phenobarbital levels by inhibiting its hepatic metabolism
• Watch for increased sedation, drowsiness, and cognitive impairment
• Phenobarbital dose reduction may be necessary
• The combination adds to the sedative burden on the patient

Carbamazepine (Tegretol)

• A bidirectional interaction: CBD may increase carbamazepine levels, while carbamazepine (a strong CYP3A4 inducer) may decrease CBD levels
• This makes dosing particularly challenging
• Monitor carbamazepine levels closely after starting CBD
• Watch for signs of carbamazepine toxicity: dizziness, double vision, nausea, ataxia

Levetiracetam (Keppra)

• The interaction between CBD and levetiracetam is less pronounced than with other AEDs because levetiracetam is primarily renally excreted rather than hepatically metabolized
• However, some patients report increased drowsiness when the two are combined
• Generally considered one of the safer combinations

Phenytoin (Dilantin)

• CBD may increase phenytoin levels through CYP2C19 inhibition
• Phenytoin has a narrow therapeutic window, meaning small changes in blood levels can cause toxicity
• Signs of phenytoin toxicity include nystagmus (involuntary eye movements), ataxia, slurred speech, and confusion
• Monitor phenytoin levels closely

Lamotrigine (Lamictal)

• The interaction with lamotrigine is not well characterized but is thought to be less significant than with clobazam or valproate
• Some practitioners report no clinically meaningful interaction
• Monitor for lamotrigine-related side effects including rash, dizziness, and headache

Summary Table of Key Interactions

Anti-Seizure Medication	Interaction Severity	Primary Concern	Action Required
Clobazam	High	Sedation from elevated norclobazam	Reduce clobazam dose 25-50%
Valproate	High	Hepatotoxicity (liver damage)	Mandatory liver function monitoring
Topiramate	Moderate	Increased topiramate side effects	Monitor and adjust as needed
Phenobarbital	Moderate	Increased sedation	Monitor and consider dose reduction
Carbamazepine	Moderate	Bidirectional interaction	Monitor drug levels closely
Phenytoin	Moderate	Narrow therapeutic window at risk	Monitor drug levels closely
Levetiracetam	Low	Mild additive drowsiness	Monitor but often no adjustment needed
Lamotrigine	Low	Minimal interaction expected	Standard monitoring

Monitoring Requirements

Epilepsy patients using CBD require more intensive monitoring than most other cannabis patients due to the drug interactions described above.

Baseline Testing (Before Starting CBD)

• Complete blood count (CBC)
• Liver function tests (ALT, AST, bilirubin, alkaline phosphatase)
• Anti-seizure medication blood levels for any medications you are currently taking where levels can be measured
• Baseline seizure diary covering at least 4 weeks before starting CBD

Ongoing Monitoring Schedule

Timepoint	Tests and Assessments
2 weeks	Seizure diary review, side effect assessment, consider AED level check if on clobazam
1 month	Liver function tests (especially if on valproate), AED blood levels, dose adjustment review
3 months	Liver function tests, AED blood levels, comprehensive seizure diary review
6 months	Full blood panel, liver function, AED levels, overall treatment efficacy assessment
Ongoing	Liver function tests every 6 months, AED levels as clinically indicated

Red Flags Requiring Immediate Medical Attention

Contact your neurologist or seek emergency care if you experience:

• Significant increase in seizure frequency or severity after starting CBD
• New seizure types not previously experienced
• Status epilepticus (a seizure lasting more than 5 minutes)
• Signs of liver toxicity: jaundice, dark urine, persistent nausea or vomiting, right upper abdominal pain
• Excessive sedation that interferes with breathing or arousal
• Allergic reaction: rash, swelling, difficulty breathing

When Cannabis Is NOT Appropriate for Epilepsy

Cannabis is not suitable for all epilepsy patients. Do not pursue cannabis treatment in the following situations:

• As a replacement for proven anti-seizure medications — CBD is an adjunctive therapy, not a first-line treatment
• Without neurologist involvement — the drug interaction profile is too complex for unsupervised use
• If you are unable to commit to the monitoring schedule — liver function tests and drug level monitoring are essential, not optional
• During pregnancy or breastfeeding — safety data are insufficient
• If using recreational THC products for seizures — unregulated THC products with unreliable dosing are dangerous for epilepsy patients
• If seizures are well-controlled on current medications — adding CBD to a successful treatment regimen introduces unnecessary risk of drug interactions
• If there is pre-existing significant liver disease — CBD may worsen hepatic function, particularly in combination with valproate

Setting Realistic Expectations

It is important to understand what CBD can and cannot do for epilepsy:

• CBD will not cure epilepsy
• Not all patients will respond
• Among those who respond, complete seizure freedom is possible but uncommon (occurring in approximately 2-5% of patients in clinical trials)
• The realistic goal for most patients is a meaningful reduction in seizure frequency and severity
• Secondary benefits such as improved alertness, mood, and quality of life are commonly reported even when seizure reduction is modest

Seizure Diary Tracking

A detailed seizure diary is essential for evaluating whether CBD is helping. Without objective tracking, it is very difficult to assess treatment response accurately.

What to Record

For every seizure:

• Date and time
• Duration (in seconds or minutes)
• Seizure type (if you can identify it)
• Severity (mild, moderate, severe)
• Triggers (if identifiable — fever, sleep deprivation, stress, missed medication)
• Recovery time (how long until the person returns to baseline)

Daily records should also include:

• All medications taken with doses and times
• CBD dose taken with time of administration
• Side effects experienced (drowsiness, appetite changes, diarrhea, mood changes)
• Sleep quality
• Overall function and alertness (rated on a simple scale)
• Rescue medication use (if any)

How to Use the Diary

• Begin tracking at least 4 weeks before starting CBD to establish a baseline seizure frequency
• Continue tracking consistently after starting CBD
• Bring the diary to every appointment
• Look for trends over weeks and months, not day-to-day fluctuations
• Your practitioner will use the diary to make dosing decisions

Paper diaries, spreadsheets, or epilepsy-specific smartphone apps are all acceptable. The best diary is one that you or your caregiver will actually use consistently.

Emergency Protocols

Starting CBD does not change the need for emergency seizure management. Every epilepsy patient and caregiver should have a clear seizure action plan.

Remain on Rescue Medications

• Do not discontinue rescue medications (such as rectal diazepam, buccal midazolam, or intranasal midazolam) when starting CBD
• CBD is a preventive therapy — it works over time to reduce seizure frequency, but it does not stop a seizure that is already occurring
• Rescue medications must remain available at all times

Seizure First Aid

In the event of a tonic-clonic seizure:

1. Stay calm and note the time
2. Protect the person from injury — clear the area of hard or sharp objects
3. Do not restrain the person or put anything in their mouth
4. Turn the person on their side (recovery position) once the jerking stops
5. Time the seizure — if it lasts more than 5 minutes, this is a medical emergency
6. Call emergency services if: the seizure lasts more than 5 minutes, the person does not regain consciousness, a second seizure follows quickly, the person is injured, or this is their first seizure

When to Call Emergency Services in Thailand

• Emergency number: 1669 (national emergency medical service)
• Seizure lasting more than 5 minutes (status epilepticus)
• Repeated seizures without recovery between them
• Seizure in water
• Injury during the seizure
• First-ever seizure
• Seizure in a pregnant woman
• Signs of respiratory difficulty after the seizure

Lifestyle Factors for Seizure Management

While CBD can be a valuable addition to epilepsy treatment, lifestyle factors play an important role in seizure control.

Sleep

Sleep deprivation is one of the most common seizure triggers. Patients should:

• Maintain a consistent sleep schedule
• Aim for 7-9 hours of sleep per night (more for children)
• Treat any underlying sleep disorders
• Avoid caffeine and stimulants in the evening

Stress Management

Stress can lower seizure thresholds. Techniques that may help include:

• Regular moderate exercise (avoid overexertion and overheating)
• Meditation and mindfulness practices
• Adequate rest and pacing of activities
• Support from family, friends, and community

Medication Adherence

Missing anti-seizure medication doses is a leading cause of breakthrough seizures:

• Use pill organizers and alarms
• Never skip a dose of conventional medication to “rely on CBD instead”
• If you miss a dose, follow your neurologist’s guidance on catch-up dosing
• Keep a backup supply of medications when traveling

Finding the Right Practitioner

For epilepsy patients, choosing the right cannabis practitioner is especially important. Look for:

• Experience with neurological conditions — not all cannabis practitioners are equally familiar with epilepsy
• Willingness to coordinate with your neurologist — this is non-negotiable for epilepsy patients
• Knowledge of drug interactions — the practitioner should be able to discuss the specific interactions between CBD and your current medications
• Conservative approach — a practitioner who emphasizes slow titration, monitoring, and CBD-dominant products for epilepsy
• Follow-up protocols — regular appointments, not just a one-time prescription

Visit our clinic directory to find licensed practitioners, and visit our medical cannabis guide for additional resources on cannabis treatment in Thailand.

Summary: Key Takeaways

1. CBD for epilepsy has the strongest evidence base in cannabis medicine — validated by randomized controlled trials and regulatory approvals
2. Epidiolex (pure CBD) is FDA-approved for Dravet syndrome, Lennox-Gastaut syndrome, and tuberous sclerosis complex
3. CBD works through multiple anticonvulsant mechanisms including GPR55 antagonism, TRPV1 desensitization, sodium channel blockade, and adenosine reuptake inhibition
4. CBD is strongly preferred over THC for epilepsy — THC carries risks of proconvulsant effects at higher doses
5. Drug interactions are significant — especially with clobazam (sedation) and valproate (liver toxicity)
6. Start low, go slow — begin at 2.5 mg/kg/day and titrate gradually over weeks
7. Monitoring is essential — liver function tests, drug levels, and seizure diaries are not optional
8. Remain on rescue medications — CBD is preventive, not a rescue treatment
9. Specialist involvement is required — epilepsy patients should never start CBD without neurologist oversight
10. Access in Thailand is available through the PT 33 system at licensed clinics

Medical Disclaimer

This article is for informational purposes only and does not constitute medical advice. Epilepsy is a serious neurological condition that carries risks of injury and death, including sudden unexpected death in epilepsy (SUDEP).

The information in this guide is based on published clinical research, international treatment guidelines, and general practitioner experience. It is not a substitute for personalized medical advice from a qualified neurologist or epilepsy specialist.

Never start, stop, or change any medication — including cannabis products — without consulting your neurologist. Never discontinue anti-seizure medications abruptly, as this can trigger life-threatening status epilepticus.

The clinical evidence for CBD in epilepsy, while strong for specific syndromes (Dravet, Lennox-Gastaut, tuberous sclerosis complex), does not guarantee benefit for all forms of epilepsy. Individual responses vary, and not all patients will experience improvement.

Cannabis products available in Thailand may differ in quality, consistency, and potency from the pharmaceutical-grade CBD (Epidiolex) used in clinical trials. This variability underscores the importance of using products from reputable sources with third-party testing.

If you or someone in your care experiences a seizure lasting more than 5 minutes, repeated seizures, difficulty breathing, or any other emergency, call 1669 immediately.