Correction: Doctors know less
about drugs than Pharmacists
. The Pharmacist
is the one with all the heavier Organic chemistry
training and pharmacy
knowledge, although doctors know a great deal too.
Ever wonder why the doctor writes a prescription for a drug, instead of just selling you a bottle of it in his office or clinic? Aside from the fact that pharmacies hold hundreds of medications and it's a hassle for one doctor to keep inventory, much less keep the rare medications before they expire, the Pharmacy holds an important safety check on medications and patient care and safety.
Pharmacists are trained in mixing drugs, making compounds and creating whatever cold+asthma+painkiller elixir recipe the doctor can throw at them. They are also trained in drug-drug interactions. Many or most drugs work fine in a combination, which is why some patients are on 6 medications per day or more. However, some have nasty side effects, and some can kill if taken together. Also, if you have an allergy to one medication, it could mean you have an allergy to an entire family of drugs. For example, a patient with a sulfur allergy can't take Bactrim (sulfamethoxazole) and the Pharmacist can get authorization to fill a substitute, like maybe a macrolide antibiotic such as Zithromax (azithromycin). A less dangerous example is certain antibiotics can cause birth control pills to stop working. The Pharmacist is the one who is trained to spot these interactions (and is often liable). All drugs leave the pharmacy at his or her discretion. (Their license is on the line if anything goes wrong).
For example, if one patient is on heart medication from his family doctor, and his psychiatrist writes a prescription for an anti-depressant, the Pharmacist is the one who noticed that the patient could get a fatal heart arrhythmia if they were taken together. Even the Pharmacy Technician should be able to spot when doctors wrote an incorrect amount of medication (70 days of antibiotics? Most likely someone either wasn't paying attention or forged it.) or when a patient tries getting duplicate therapies (like the patient who is on Prozac and his other doctor gave him a Celexa presciption). Also, the patient who managed to trick half the doctors in town into giving him Vicodin or narcotics will eventually get noticed by a Pharmacist when he or she glances at the patient's history before getting the pills from the safe. You could also be cynical and say that Pharmacies are useful to insurance companies by squeezing a few more premiums out of patients, but that's another story.
I also think doctors prefer pharmacies, because if they don't have encyclopedic knowledge, they'll call up the pharmacy and ask for help sometimes. "The patient can't take Altace or their insurance doesn't cover it. What is a good generic ACE inhibitor that you have?" Also, the Pharmacist is often the one who has to explain and decode the instructions to the patient.
If you ever want to see just how much the Doctor and Pharmacist have to understand before they can team up to give you medication, flip randomly through some pages of the Physicians Desk Reference. It's a massive tome that lists every drug insert for every medication on the market in America, and is written so thickly and complicated that you'll pay a doctor and pharmacist to put it in English for you. If you can't find one (and it's unlikely you would, they're very pricey and/or require a DEA number), just go open one of those small folded drug inserts you find in boxes of prescription medication, and see if you can understand some of the jargon. Pharmacists are required by law to offer counsel to patients and try to answer those questions.