Greenhead Clinic Khaosan Road

Greenhead Clinic, Khao San Road

Greenhead Clinic is a cannabis outlet at 149 Thanon Tanao, Wat Bowon Niwet, Phra Nakhon, a few steps from Khao San Road. Its own description calls it a medical marijuana shop offering consultations, and its listed hours run from noon until 1:00. We have not verified its licence status.

Buying Near Khao San

Khao San is where leftover retail-style cannabis shops are most common in Bangkok, so check for the licence-status sticker and a practitioner on duty. A legal outlet will assess you and issue or check a PT 33 before selling flower. Smoking on the street is a Public Health Act offence with fines up to 25,000 THB. Our guide to medical-grade cannabis in Bangkok covers the rest of the city.

PT 33 Prescription Note

Since 26 June 2025, cannabis flower in Thailand is a controlled herb and may only be sold against a PT 33 prescription (ใบสั่งยา ปท. 33) from an authorised practitioner. Recreational sale is illegal, whatever a shop’s signage says, and a legitimate outlet will ask for your prescription before selling flower. CBD products at or below 0.2% THC are the only cannabis products sold without one. Call ahead to confirm a certified practitioner is on duty, and bring your passport or Thai ID. Our PT 33 prescription guide explains the consultation. For other outlets nearby, see cannabis clinics and dispensaries in Bangkok.