AMA ON PHENYLPROPANOLAMINE

AMA ON PHENYLPROPANOLAMINE: The American Medical Association (AMA) is delaying a decision to formulate "guidelines for use of [phenylpropanolamine] in diet preparations until [FDA] studies are complete," the assn. says. At that time, FDA will publish a tentative final monograph in the Federal Register under OTC review procedures and "the AMA may elect to respond to this document and to develop guidelines" for phenylpropanolamine use. AMA will submit a report on phenylpropanolamine to its House of Delegates at the June 15-19 annual meeting in Chicago. The study was generated by a resolution passed at the 1985 AMA annual meeting, recommending that the assn. "study the effects" of phenylpropanolamine in OTC preparations and "develop guidelines for its use." AMA found that: "Severe hypertensive complications in patients taking [phenylpropanolamine] have usually resulted from ingestion of large or unknown doses, often taken with other sympoathomimetic drugs. Pressor effects from the usual recommended dose may occur in patients with pre-existing hypertension or autonomic dysfunction and in those concurrently taking indomethacin, monoamine oxidase inhibitors, foods containing tyramine, certain antihypertensive drugs, and possibly oral contraceptives . . . The pressor effect of sustained-release products is slight and variable." In 1982, the FDA published an advance notice of proposed rulemaking on OTC weight control drugs, based on recommendations of the FDA Advisory Review Panel on OTC Miscellaneous Drug Products. The Panel's report concluded that phenylpropanolamine is safe and effective as an appetite suppressant when used for up to 12 weeks in conjunction with reduced caloric intake. The Panel also proposed that the maximal recommended dose be increased from 37.5 to 50 mg for single-dose, immediate-release preparations and from 75 to 150 mg for sustained-release preparations. In its report to the 1986 House of Delegates, AMA notes that: "FDA delayed acceptance of the Panel's recommendations until certain questions of safety were resolved. Specifically, FDA sought further information on the extent to which [phenylpropanolamine] induces hypertension in normotensive individuals, aggravates pre-existing hypertension, and interacts with other durgs to increase blood pressure when given at dose levels recommended by the Panel. Information on dissolution rates of substained-release products was also requested." The AMA report cites FDA studies addressing these questions that are now in progress: (1) A tolerance study employing increasing doses of an immediate-release preparation; (2) a study designed to determine whether a dose of [phenylpropanolamine] that initially increases blood pressure continues to do so with long-term administration; (3) a study of the safety of [phenylpropanolamine] in obese patients with hypertension.