Pharmacies, Medication Distribution in Bangkok
You never need to walk more than a few hundred meters to find a pharmacy in Bangkok. Prescriptions are seldom used, most of business is be done over the counter. While standards differ, pharmacists themselves are not always on the premises.
When visiting hospitals, one is referred to the hospital pharmacy to get needed drugs. No prescriptions are given, the physician just writes his prescriptions on some internal paper for the hospital pharmacy.
We do not even know whether one can ask specifically for a prescription to be used at an outside pharmacy or not. In any case, be reminded that pharmacies at major hospitals charge (much) more for drugs than outside-hospital pharmacies. (more about this topic)
If you are on long-term treatment with a particular drug, it is maybe useful to just get it without prescription outside, and tell your physician you have a supply of drugs of your own. Most physicians know the reason, and have no objections.
Generic drugs can be obtained at a fraction of the cost of 'brand name' drugs. However, only in pharmacies outside major hospitals.
Sedatives - Recreational Drugs
Commonly used drugs are widely available in Bangkok. For sure, do not be surprised if a particular drug, just released in U.S.A. or Europe, is not yet available. Up to about 10 years ago, it was possible to just get about anything without prescription, including antibiotics, sedatives, anti-depression medication, recreational drugs like Viagra etc. In many cases this may not have been strictly according to the law, but in practice there were no obstacles in obtaining what you wanted.
At present, it is more difficult or impossible to get sedatives or psycho-active drugs without prescription. We do think that recreational drugs like Viagra still can be obtained, when discreet.
30 June 2013 seems to have been a turning point for the availability of sedatives and sleeping pills. We understand, and the pharmacies are well aware of it, that potent sedatives and sleeping pills will stop being provided without prescription (maybe this was already so before, but pharmacies have been warned apparently of stricter enforcement). Maybe this is for the better, after all it was recently revealed that sleeping pills increase mortality (make it more likely you die prematurely). Valium, and possible some other milder sedatives, are still available. This being said, some pharmacy operators, will likely continue to provide drugs illegitimately at a high price.
Viagra and other drugs for erectile dysfunction (these drugs are more likely used in Bangkok for recreational purposes) are widely available the length of Sukhumvit road, presented on easily removed little tables, often with the sun blasting overhead. At one time, the GPO (Governmental Pharmacy Organization of Thailand) planned to produce its own version of Viagra, we don't know if it ever happened. The sidewalk business goes up and down. Occasionally all stalls will disappear, and reappear a few months later.
Antibiotics, drugs for high cholesterol, cardiac medication, anti-rheumatic drugs etc. can still be bought over the counter.
Do not expect a lot of communication with the average pharmacist.
One of the main functions of a pharmacist should be to explain how and when medicine needs to be taken, and to check for interactions with other drugs. Now, especially the latter hardly ever happens. If you just ask for a certain medication on the counter, there is a risk of misunderstanding, and you may end up with something with a similar name, but different function. It is useful to write down the name of the medication you need. Always ask for a generic version (if you are OK with that), since the pharmacy operator benefits more from selling you the 'original' medication. Quite a few of the standard medication for diabetes, heart disease, cholesterol, are produced in Thailand as generic drugs.
A lot of pharmacists simply perform the function of a salesperson, and nothing more. If you are familiar with your medication, this may be fine. Otherwise, you may be better off at hospital pharmacies (the pharmacists there at least explain a bit more, and if asked, they will certainly check out any drug interactions).
Pharmacies, continued : recommended pharmacies, regarding prescription drugs