Neosinephrine-POS^® (Drops) Instructions for Use

ATC Code

S01FB01 (Phenylephrine)

Active Substance

Phenylephrine (Rec.INN registered by WHO)

Clinical-Pharmacological Group

Topical alpha-adrenergic agonist for use in ophthalmology

Pharmacotherapeutic Group

Alpha-adrenomimetic

Pharmacological Action

Sympathomimetic. It has pronounced alpha-adrenergic activity and, when used in usual doses, does not have a significant stimulating effect on the central nervous system.

When used topically in ophthalmology, it causes pupil dilation, improves the outflow of intraocular fluid, and constricts the vessels of the conjunctiva.

Phenylephrine has a pronounced stimulating effect on postsynaptic α-adrenergic receptors and has a very weak effect on myocardial β-adrenergic receptors. The drug has a vasoconstrictor effect similar to that of norepinephrine, while it has practically no chronotropic and inotropic effects on the heart. The vasopressor effect of phenylephrine is less pronounced than that of norepinephrine but is more prolonged. It causes vasoconstriction within 30-90 seconds after instillation; the duration of action is 2-6 hours.

After instillation, Phenylephrine contracts the pupil dilator and the smooth muscles of the conjunctival arterioles, thereby causing pupil dilation.Mydriasis occurs within 10-60 minutes after a single instillation. Because Phenylephrine has a slight effect on the ciliary muscle, mydriasis occurs without cycloplegia.

Pharmacokinetics

Phenylephrine easily penetrates the eye tissues; C_max in plasma is reached within 10-20 minutes after topical application. Phenylephrine is excreted by the kidneys unchanged (<20%) or as inactive metabolites.

Indications

Iridocyclitis (to prevent the formation of posterior synechiae and reduce exudation from the iris); for diagnostic pupil dilation during ophthalmoscopy and other diagnostic procedures necessary to monitor the condition of the posterior segment of the eye; performing a provocative test in patients with a narrow anterior chamber angle and suspected angle-closure glaucoma; differential diagnosis of superficial and deep injection of the eyeball; in ophthalmic surgery – for preoperative preparation for pupil dilation; for pupil dilation during laser interventions on the fundus and in vitreoretinal surgery; treatment of glaucomatocyclitic crises; treatment of the “red eye” syndrome to reduce hyperemia and irritation of the eye membranes; accommodative spasm.

ICD codes

Dosage Regimen

Instill one drop into the conjunctival sac of the affected eye(s). The specific regimen is determined by the indication and the concentration of the solution used.

For diagnostic mydriasis during ophthalmoscopy, use the 2.5% solution. Apply one drop approximately 15-60 minutes before the examination. For more pronounced mydriasis, particularly in patients with darkly pigmented irides, the 10% solution may be used under medical supervision.

For preoperative mydriasis in ophthalmic surgery, apply one drop of the 10% solution. This is typically administered in conjunction with other mydriatic agents, such as anticholinergics, as directed by the surgeon.

In the management of iridocyclitis, apply one drop of the 2.5% solution to the affected eye up to three times daily. This regimen helps prevent the formation of posterior synechiae.

For the relief of ocular redness in the “red eye” syndrome, apply one drop of the 0.12% solution to the affected eye(s) up to four times daily. Limit use to a short duration, typically 72 hours.

To perform a provocative test in patients with narrow anterior chamber angles, instill one drop of the 2.5% or 10% solution. Monitor intraocular pressure closely before and after the procedure.

Do not touch the dropper tip to any surface to avoid contamination. Wait at least five minutes before instilling any other topical ophthalmic medications.

Adverse Reactions

From the organ of vision: conjunctivitis, periorbital edema; possible burning sensation at the beginning of use, blurred vision, irritation, discomfort, lacrimation, increased intraocular pressure.

Due to significant contraction of the pupil dilator under the influence of phenylephrine, 30-45 minutes after instillation, pigment particles from the pigment layer of the iris may be detected in the aqueous humor of the anterior chamber. The suspension in the aqueous humor must be differentiated from the appearance of anterior uveitis or the entry of blood cells into the aqueous humor of the anterior chamber.

From the cardiovascular system: possible palpitations, tachycardia, arrhythmia (including ventricular), arterial hypertension, reflex bradycardia, coronary artery occlusion, pulmonary embolism.

Dermatological reactions: contact dermatitis.

Contraindications

Angle-closure glaucoma; elderly patients with serious disorders of the cardiovascular system and cerebral circulation; for additional pupil dilation during surgical operations in patients with impaired integrity of the eyeball, as well as with impaired tear production; arterial aneurysm (eye drops 10%); hyperthyroidism; hepatic porphyria; childhood (depending on the dosage form used).

Use in Pregnancy and Lactation

Since the effect of phenylephrine for eye instillation during pregnancy and lactation has not been sufficiently studied, use in these patients is possible only in cases where the expected benefit of therapy for the mother outweighs the potential risk to the fetus or infant.

Use in Hepatic Impairment

Contraindicated in hepatic porphyria.

Pediatric Use

Used in children in appropriate dosage forms.

Geriatric Use

Contraindication: elderly patients with serious disorders of the cardiovascular system and cerebral circulation.

Special Precautions

Phenylephrine should be used with caution in patients with diabetes mellitus due to the risk of developing increased blood pressure associated with autonomic regulation disorders, as well as in elderly patients – due to an increased risk of reactive miosis.

Should be used with caution simultaneously with MAO inhibitors, as well as within 21 days after their discontinuation.

Exceeding the recommended dose in patients with injuries, diseases of the eye or its appendages, in the postoperative period, or with reduced tear production (anesthesia) may lead to increased absorption of phenylephrine and the development of systemic side effects.

Because Phenylephrine, when applied topically, causes conjunctival hypoxia, it should be used with caution in patients with sickle cell anemia, when wearing contact lenses, and after surgical interventions (impaired healing).

Drug Interactions

The mydriatic effect of phenylephrine is enhanced when used in combination with atropine. Due to the enhancement of the vasopressor action, tachycardia may develop.

When used simultaneously with MAO inhibitors or within 21 days after their discontinuation, there is a risk of an uncontrolled increase in blood pressure.

The vasopressor action of adrenomimetic agents can also be potentiated when used concomitantly with tricyclic antidepressants, propranolol, reserpine, guanethidine, methyldopa, and m-cholinergic blockers.

The use of phenylephrine in the form of 10% eye drops in combination with systemic use of beta-blockers may lead to acute arterial hypertension.

Phenylephrine may potentiate the depressant effect on the activity of the cardiovascular system during inhalation anesthesia.

Concomitant use with sympathomimetics may enhance the cardiovascular effects of phenylephrine.

Storage Conditions

Store at 2°C (36°F) to 25°C (77°F). Keep in original packaging, protected from light. Keep out of reach of children.

Dispensing Status

Rx Only

Important Safety Information

This information is for educational purposes only and does not replace professional medical advice. Always consult your doctor before use. Dosage and side effects may vary. Use only as prescribed.