Fate of a ferrous sulfate prescription.

Prescriptions for ferrous sulfate, 300 mg, were filled with eight different preparations by 15 pharmacies. Only three types of pills had a reasonably rapid dissolution time in acid media and these were all obtained from university-associated pharmacies. Some form of "slow release" or "enteric coat" feature was present in the pills and capsule supplied by private pharmacies and the Veterans Administration Hospital pharmacy. Adding the phrase "not enteric-coated" to the prescription effected no change in the type of pill supplied. Prices were highly variable, even for the same preparation, and although all generic pills were cheaper than brand-name pills, the "supermarket" type pharmacies charged as much or more for the pills as individually owned pharmacies.