Possible adverse effects from topical ocular 10% phenylephrine

The authors studied 33 cases of adverse side effects possibly related to ocular 10% phenylephrine application drawn from case reports submitted to the National Registry of Drug-Induced Ocular Side Effects. These cases included 15 myocardial infarcts, 11 of which were terminal; in 7 additional cases cardiopulmonary resuscitation was necessary, and the remainder primarily included marked increase of blood pressure. It is concluded that if these responses were drug-related, predisposing factors may have included overdosage of the drug, cardiac disease, advanced age, and drug interactions. Myocardial infarcts occurred primarily in older patients with preexisting cardiac disease. This type of population would have an increased incidence of myocardial infarcts regardless of topical ocular medication. The authors' results did not prove a positive correlation between 10% phenylephrine and myocardial infarcts. However, based on these case reports, the amount of drug delivered, and the drug's known cardiovascular effects, they formulated possible guidelines for the clinical use of topical ocular 10% phenylephrine. To date, no significant adverse effects have been reported to the National Registry of Drug-Induced Ocular Side Effects with the ophthalmic use of 2.5% phenylephrine hydrochloride. Six additional cases of adverse reactions related to 10% phenylepinephrine have come into the Registry since this article was written.