Abstract The effectiveness of 1% pilocarpine in counteracting the mydriatic effect of phenylephrine hydrochloride (Neo-Synephrine Hydrochloride), hydroxyamphetamine hydrobromide (Paredrine), tropicamide (Mydriacyl), and homatropine hydrobromide in the concentrations ordinarily used in clinical ophthalmology was studied in 15 subjects. Pupillary diameters were measured with the infrared electronic pupillograph. It was found that the mydriatic effects of the sympathomimetic drugs (phenylephrine and hydroxyamphetamine) are rapidly counteracted by pilocarpine, usually in much less than 30 minutes. However, after mydriasis with parasympatholytic drugs (tropicamide and homatropine), pilocarpine produced little effective miosis and the pupil remained dilated or semidilated for a prolonged period. References 1. Mayer, L.L.: Dilation of the Pupil for Ophthalmoscopic Examination , JAMA 113:38-39 ( (July 1) ) 1939.Crossref 2. Feldman, J.B.: Mydriatics: A Clinical Observation , Arch Ophthal 41:42-59 ( (Jan) ) 1949.Crossref 3. Gambill, H.D.; Ogle, K.N.; and Kearns, T.P.: Mydriatic Effect of Four Drugs Determined With Pupillograph , Arch Ophthal 77:740-746 ( (June) ) 1967.Crossref 4. Ogle, K.N.; Whisnant, R.A.; and Hazelrig, J.B.: Quantitative Study of Pupil Response to Miotic Drugs , Invest Ophthal 5:176-185 ( (April) ) 1966. 5. Lowenstein, O., and Loewenfeld, I.E.: Electronic Pupillography: A New Instrument and Some Clinical Applications , Arch Ophthal 59:352-363 ( (March) ) 1958.Crossref 6. Thompson, H.S.: Afferent Pupillary Defects: Pupillary Findings Associated With Defects of the Afferent Arm of the Pupillary Light Reflex Arc , Amer J Ophthal 62:860-873 ( (Nov) ) 1966. 7. Lowenstein, O., and Loewenfeld, I.E.: " The Pupil ," in Davson, H. (ed.): The Eye , New York: Academic Press, Inc., 1962, vol 3, pp 231-267. 8. Lowenstein, O.: Pupillary Reflex Shapes and Topical Clinical Diagnosis , Neurology 5:631-644 ( (Sept) ) 1955.Crossref 9. Lowenstein, O., and Loewenfeld, I.E.: Disintegration of Central Autonomic Regulation During Fatigue and Its Reintegration by Psychosensory Controlling Mechanisms: I. Disintegration: Pupillographic Studies , J Nerv Ment Dis 115:1-21 ( (Jan) ) 1952.Crossref 10. Lowenstein, O., and Loewenfeld, I.E.: Influence of Retinal Adaptation Upon the Pupillary Reflex to Light in Normal Man: Part I. Effect of Adaptation to Bright Light on the Pupillary Threshold , Amer J Ophthal 48:536-549 ( (Nov) ) 1959. 11. Lowenstein, O., and Loewenfeld, I.E.: Influence of Retinal Adaptation Upon the Pupillary Reflex to Light in Normal Man: Part II. Effect of Adaptation to Dim Illumination Upon Pupillary Reflexes Elicited by Bright Light , Amer J Ophthal 51:644-654 ( (April) ) 1961.
Archives of Ophthalmology – American Medical Association
Published: Jun 1, 1968