PIP: Potential risks of prescribing generic drugs for oral contraception, ovulation induction and menopausal estrogen substitution are reviewed. In the U.S. all 50 states permit or require generic substitution, unless the prescription states otherwise. F.D.A. guidelines allow the bioavailability to range within 25%, i.e., the circulating level of drug in male test subjects after a single dose must be within + or - 25% of the range reported with the pioneer drug. Thus if a patient renews her prescription monthly she may receive a 50% range in dose level if different generics with both extremes in bioavailability are provided. Potential ranges for women, ill or elderly may vary even more. The potential risks for oral contraceptives are unwanted pregnancy, breakthrough bleeding, blood lipid elevation and less serious consequences such as minor side effects or confusion over package design. Risks for generic estrogen replacement include lack of protection from cardiovascular disease or osteoporosis and lack of therapeutic effect on menopausal symptoms; those from progestins are atherogenesis and failure to stop dysfunctional bleeding, ending in an unnecessary D & C. Possible sequelae of generics for ovulation induction are multiple pregnancy and ovarian hyperstimulation resulting in hospitalization for acute massive ovarian enlargement or rupture, as well as extra months of expense for treatment and monitoring. The most pressing concern is liability for the physician or pharmacist related to provision of generics. In most cases even 1 additional office visit for drug dose adjustment will obviate all savings accrued from taking generics.