Cannabis and Sex: Evidence on Desire, Erections and the Risks

Many patients ask me, "Does cannabis really make sex better?" Some have heard it helps them relax; others worry it stops them getting hard. The evidence-based answer is: it depends on many things, and there is no clear conclusion yet. This article is part of the series What is chemsex and how to reduce harm. It does not recommend cannabis or explain how to use it, but it helps you decide based on real information.

Thailand's legal situation in brief

As of October 2026, Thailand removed cannabis from its narcotics list on 9 June 2022, but it has been progressively re-regulated since then. A Ministry of Public Health notification on controlled herbs (cannabis) in June 2025 made it possible to buy cannabis flower only with a prescription from a recognised practitioner. On 22 September 2026 the Cabinet approved in principle a draft Cannabis Control Act that would limit cannabis to medical use and research only. At the time of writing, the bill is still before Parliament.

In short, cannabis in Thailand is not freely available for recreational use. The rules change quickly, so always check the latest regulations, and never drive after using it. Visitors should not assume cannabis is "legal for recreation" in Thailand.

How cannabis acts on the body

The main compounds are THC, which produces the "high", and CBD, which doesn't make you high but does affect the nervous system and other medicines. Both act through the endocannabinoid system, which is involved in mood, pain and sexual response. Effects vary greatly from person to person, depending on product strength, the THC-to-CBD ratio, expectations and state of mind at the time. Edibles act slowly and last a long time, so people often end up with too much.

The evidence on desire, erections and orgasm

• Frequency and desire. A US population survey (Sun and Eisenberg, 2017) found that cannabis users had sex slightly more often than non-users, but it was a cross-sectional study, so it cannot show that cannabis was the cause.
• Women and orgasm. A study of 373 women (Lynn and colleagues, 2019) found that those who used cannabis before sex reported higher satisfaction with orgasm, but it was a questionnaire from a single clinic.
• Men and erections. A meta-analysis (Pizzol and colleagues, 2019) found ED was roughly twice as common in men who smoked cannabis, but the studies varied widely, so the evidence is uncertain.
• Ejaculation and hormones. There are reports of both premature and delayed ejaculation, and regular use is linked to lower sperm counts and testosterone. Read supporting testosterone through sleep, diet and exercise.

In summary, some people feel more relaxed and sensitive to touch, while others become anxious or find erections worse, especially heavy and regular users. There is no medical indication for using cannabis to treat sexual problems.

What some studies found

• Slightly more frequent sex
• Some women report more satisfying orgasms
• Some people feel more relaxed

What to watch out for

• ED about twice as common in smokers
• Sperm and testosterone may fall
• Anxiety or paranoia in some

vs

Mostly cross-sectional studies, which cannot show cause and effect (Sun 2017, Lynn 2019, Pizzol 2019).

The risks you should know

• Palpitations, anxiety or paranoia, especially with high-THC products and edibles, which act slowly, so many people end up with too much.
• Psychotic symptoms in people at risk, such as those with a family history of schizophrenia or who started using young.
• Dependence (cannabis use disorder) is real in regular users, and some develop bouts of severe vomiting after long-term use (cannabinoid hyperemesis syndrome).
• Combining with alcohol or other drugs increases impairment and worsens decisions about condoms and consent.
• Smoking irritates the airways and affects blood vessels.
• Pregnancy or breastfeeding: best avoided.

Reducing harm. Be especially careful with edibles, don't mix with alcohol or other drugs, don't drive, and avoid cannabis if you have a history of psychosis or bipolar disorder.

Drug interactions to know about

• Erection medicines (PDE5 inhibitors). Cannabis raises heart rate and changes blood pressure; together they may cause dizziness or fainting. People with heart disease should be especially careful.
• Sleeping pills, anti-anxiety medicines, opioid painkillers and alcohol add to drowsiness and slowed breathing.
• Medicines processed by liver enzymes. CBD and THC can change the levels of some medicines, such as warfarin, some anti-seizure medicines and psychiatric medicines.
• HIV medicines and PrEP. Interactions are mostly minor, but tell your doctor, and make sure using doesn't lead to missed doses.
• Combining with other chemsex drugs makes the effects even less predictable. Read crystal meth, yaba, ketamine and G in chemsex.

Cannabis

Erection medicines

• Faster heart rate, BP changes
• Possible dizziness, fainting

Sedatives, alcohol

• More drowsiness
• Slowed breathing

Liver-enzyme drugs

• Warfarin
• Some anti-seizure, psychiatric drugs

HIV medicines / PrEP

• Mostly minor interactions
• Watch for missed doses

Always tell your doctor if you use cannabis or CBD.

When to see a doctor

• You feel you can't have sex without cannabis, or you are using more and more often.
• You have problems with erections, ejaculation or low desire. Read erectile dysfunction (ED) and low sexual desire.
• You feel anxious or paranoid, or hear voices (Thailand's mental-health hotline 1323; Thai language, ask for English support).
• You have recurrent bouts of severe vomiting.
• Severe palpitations, chest pain or fainting: call 1669 immediately.

How Dr. Kris can help

At Dr. Kris Clinic we can talk about cannabis openly and without judgement, assess any related sexual problems, check interactions with your current medicines, and help with the performance anxiety that some people use cannabis to cover up. Read sexual performance anxiety. We refer you on when needed. Consultations are available at the clinic and online, including in English.