Systemic absorption of topically applied ocular atropine.

We quantitated atropine plasma levels and monitored blood pressure, heart rate, and salivary secretion after ocular application. Eight patients received 40 microliters 1% atropine in the lower cul-de-sac of one eye in connection with ocular surgery. Atropine plasma levels were determined for 90 minutes by radioreceptor assay. The peak plasma atropine concentration of 860 +/- 402 pg/ml was reached within 8 minutes in all patients. The ocular absorption of atropine was at least as rapid as that reported for intramuscular administration. Ocular atropine did not affect patients' blood pressure or heart rate when compared with those of the placebo group. Thirty minutes after administration of atropine eyedrops, the salivary secretion in the experimental group was reduced, but was statistically insignificant from the placebo group.