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ARTICLES |
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Year : 1975 | Volume
: 23
| Issue : 1 | Page : 16-17 |
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Systemic effects of topical phenylephrine
S Samantary, A Thomas
Department of Ophthalmology, Christian Medical College, Vellore, India
Correspondence Address: S Samantary Department of Ophthalmology, Christian Medical College, Vellore India
Source of Support: None, Conflict of Interest: None | Check |
PMID: 1158416
How to cite this article: Samantary S, Thomas A. Systemic effects of topical phenylephrine. Indian J Ophthalmol 1975;23:16-7 |
The sympathomimetic drugs are widely used in ophthalmology and are usually regarded as harmless. Among them phenylephrine hydrochloride (drosyn) 10% is commonly used in routine ophthalmic practice as a mydriatic and vasoconstrictor agent. This is usually considered to be safe except in patients with narrow angle glaucoma but reports in the literature suggest that there may be definite hazard like acute episodes of systemic hypertension after the topical use of 10% phenylephrine hydrochlorides [5] . McReynolds et al [6] reported a patient who developed subarachnoid haemorrhage after a cotton pack soaked in 10% phenylephrine was applied to one of his eyes. The present study is undertaken with a view to assess the systemic effect of phenylephrine from topical application.
Materials and Methods | | |
The present study includes the patients attending the department of ophthalmology (Schell Eye Hospital) of Christian Medical College, Vellore from January 1974 to April 1974. Total number of cases studied were 60, 30 hypertensive patients and 30 normotensive, age and sex matched. Patients with narrow angle glaucoma and diastolic blood pressure above 125 mmHg. were exempted from the study.
In every case blood pressure and pulse rate were recorded before instillation of phenylephrine. Then one drop of 10% phenylephrine hydrochloride was instilled into the conjunctival cul-de-sac of both eyes at 10 minutes interval for three times. Blood pressure and pulse were again recorded exactly 30 minutes after instillation.
Results | | |
Age : Age composition of the series is shown in [Table - 1]. Most of the hypertensive patients (60%) belong to the age group between 40 to 49 years. In the normotensive group also the majority (66.6%) belong to the same group.
Sex : Out of 60 cases, 46 were males and 14 were females.
Blood Pressure and heart rate : In both the groups after phenylephrine instillation a rise in blood pressure was observed. Systolic and diastolic blood pressure rose by about 10 to 40 mmHg and 10 to 30mmHg respectively in all the cases. No untoward side effects like palpitation, sweating, trembling and fainting attacks were seen in any case. Associated with rise in blood pressure there occurred slowing of the heart rate by 10 to 20/'minute in all the cases.
Discussion | | |
Phenylephrine hydrochloride (Neo-Synephrine hydrochloride), the levoisomer of 3-hydroxyphenyl-ethanol-methylamine is a sympathomimetic drug which differs chemically from epinephrine by the absence of hydroxyl group in the position of 4 benzene ring. It is a powerful alpha receptor stimulant with little effect on the beta-receptors. Clinical applications of the drug depend on the alpha activity. It mainly acts directly on the receptors. It also stimulates the release of norepinephrine.
Parenteral administration in human beings produces peripheral vasoconstriction, rise in both systolic and diastolic blood pressure and marked reflex cardiac slowing. There is no inotropic or chronotropic effect on heart like seen with a norepinephrine. It increases the arterial pressure by peripheral vasoconstriction and not by myocardial stimulation [2] .
Topically administered phenylephrine can primarily be absorbed into the circulation in three ways (1) by the conjunctival vessels (2) by anterior segment of the eye and by (3) nasal and oral mucosa to produce systemic reaction. The resulting systemic effect from absorption to the circulation was first noted by Heath [3] He first described the uses of phenylephrine in ophthalmology and noted that when the drug was applied to a dog cornea in powder form, it caused an abrupt and pronounced rise in blood pressure. He warned therefore that care should be taken in the use of drug in patients with arteriosclerosis and hypertension. Richard` reported severe occipital headache, palpitation, hypertension (upto 230 mmHg systolic), trembling and excessive perspiration in a patient after the use of topical phenylephrine.
Our observation supports the statement of Heath and Geiter [4] who acknowledged that rapid absorption of substantial amount of the drug "causes marked and hazardous increase of the blood pressure". Significant increase in blood pressure both systolic and diastolic and reflex bradycardia were noted in all the patients in the present series after the topical use of the drug. This shows that absorption of phenylephrine from topical use though slow and limited can cause systemic elevation of blood pressure both in normal and hypertensive patients. But no patient in the series had abrupt rise in blood pressure nor had any systemic side reaction as reported by Richard and Jacob [5] . Probably those symptoms were due to Idiosyncracy to the drug. However, phenylephrine is no doubt a potentially dangerous drug in causing rise in systemic blood pressure even on topical application. Hence it should be contraindicated or used with caution in hypertensive patients.
Summary | | |
The blood pressure and pulse are recorded before and after instillation of 10% phenylephrine hydrochloride in the conjunctival cul-de-sac of 30 normal and 30 hypertensive patients. It is concluded that there is a definite increase in blood pressure and slowing of the heart rate after the local use of phenylephrine.[7]
References | | |
1. | Beckmann (1958) in "Drugs their nature, action and use". |
2. | Goodman, L. S., and Gillman, A. 1970, "The Pharmacological basis of Therapeutics", New York, McMillon. |
3. | Heath, P. (1936) Arch. Ophthal. 16, 839. |
4. | Heath, P. and Geiter, C. W., 1949, Arch. Ophthal. 31, 172. |
5. | Jacob T. Wilensky and Woodward Jackson, H, 1973, Amer. J. Ophthal. 76, 156. |
6. | McReynolds, W. V., Havner, W.H. and Hand erson, J. W., 1956, Arch. Ophthal. 56, 176. |
7. | Richard, K, Lenche 1966, Amer. J. Ophthal. 61, 95. |
[Table - 1]
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