Phenylephrine hydrochloride

Description

Phenylephrine Hydrochloride Ophthalmic Solution, USP is a sterile, clear, colorless to yellow topical α-adrenergic agonist intended for ophthalmic use. The active ingredient is (R)-3-hydroxy-α(methylamino)methylbenzenemethanol hydrochloride, with a molecular formula of C₉H₁₃NO₂·HCl and a molecular weight of 203.67 g/mol.

The formulation is available in two concentrations: a 2.5% solution and a 10% solution. Each mL of the 2.5% solution contains 25 mg of Phenylephrine Hydrochloride, along with inactive ingredients including Sodium Phosphate Monobasic, Sodium Phosphate Dibasic, and Water for Injection. The pH is adjusted to a range of 4.0 to 7.5 using Phosphoric Acid and/or Sodium Hydroxide, and the solution has a tonicity of 340 mOsm/kg. Benzalkonium Chloride is included as a preservative at a concentration of 0.1 mg (0.01%).

Each mL of the 10% solution contains 100 mg of Phenylephrine Hydrochloride, with the same inactive ingredients and pH adjustment as the 2.5% solution. The tonicity of the 10% solution is 985 mOsm/kg, and it also contains Benzalkonium Chloride at 0.1 mg (0.01%) as a preservative.

Uses and Indications

Phenylephrine Hydrochloride Ophthalmic Solution is indicated for the dilation of the pupil.

There are no teratogenic or nonteratogenic effects associated with this drug.

Dosage and Administration

For patients aged 1 year and older, one drop of Phenylephrine Hydrochloride Ophthalmic Solution (available in 2.5% or 10% strength) should be applied to the conjunctival fornix at intervals of 3 to 5 minutes, with a maximum of 3 drops per eye. For those requiring a greater degree of mydriasis, the 10% strength is recommended.

In pediatric patients under 1 year of age, one drop of the 2.5% strength should be instilled into the conjunctival fornix at 3 to 5 minute intervals, also with a maximum of 3 drops per eye.

Contraindications

The 10% strength is contraindicated in patients with hypertension or thyrotoxicosis due to the potential for exacerbating these conditions. Additionally, it is contraindicated in pediatric patients less than 1 year of age because of an increased risk of systemic toxicity.

Warnings and Precautions

Topical ophthalmic use is the only approved route for administration; this product is not intended for injection.

Healthcare professionals should be aware of the potential for serious cardiovascular reactions associated with the 10% strength formulation. These reactions may include ventricular arrhythmias, some of which have resulted in fatal outcomes. It is imperative to monitor blood pressure in patients with pre-existing cardiovascular disease to mitigate risks.

Significant elevations in blood pressure have been observed, particularly in pediatric patients under the age of 5, as well as in individuals with cardiovascular disease or hyperthyroidism. For patients identified as high risk, it is recommended to monitor blood pressure following treatment to ensure patient safety.

Additionally, rebound miosis has been reported as a potential effect occurring one day after instillation. Healthcare providers should be vigilant in monitoring for this reaction and counsel patients accordingly.

Side Effects

Patients may experience a range of adverse reactions associated with the use of this medication, categorized by seriousness and frequency.

Serious cardiovascular reactions have been reported, particularly with the 10% strength formulation. These include ventricular arrhythmias, some of which have been fatal, as well as myocardial infarction, syncope, tachycardia, arrhythmia, and subarachnoid hemorrhage. Additionally, a rapid rise in blood pressure has been noted in cases of overdosage, which may also lead to headache, anxiety, nausea, and vomiting.

Common ocular adverse reactions include eye pain and stinging upon instillation, temporary blurred vision, and photophobia. Furthermore, rebound miosis has been reported one day after instillation, indicating a potential for transient effects following treatment.

Healthcare professionals should monitor patients for these adverse reactions and manage them appropriately, particularly in those receiving higher concentrations of the medication.

Drug Interactions

The concomitant use of atropine-like drugs may lead to an exaggerated adrenergic pressor response. Clinicians should exercise caution when prescribing these agents together, as the enhanced response could result in significant cardiovascular effects.

Additionally, the use of potent inhalation anesthetic agents in conjunction with this medication may potentiate cardiovascular depressant effects. It is advisable to monitor cardiovascular status closely in patients receiving both the medication and inhalation anesthetics to mitigate potential risks. Adjustments to dosage or anesthetic management may be necessary based on the patient's response.

Packaging & NDC

The table below lists all NDC Code configurations of Phenylephrine Hydrochloride, the U.S. brand-name prescription product. Columns show Packaging, Formulation Type, and Active Ingredient Strength.

Pediatric Use

Phenylephrine hydrochloride ophthalmic solution 10% is contraindicated in pediatric patients less than 1 year of age. Caution should be exercised when considering the use of this medication in children, and healthcare professionals should evaluate the risks and benefits in this population.

Geriatric Use

Elderly patients have been evaluated in clinical studies, and no overall differences in safety and effectiveness have been observed when compared to younger adult patients. Therefore, dosage adjustments based solely on age are not necessary.

However, it is important for healthcare providers to consider the individual health status and comorbidities of geriatric patients, as these factors may influence the overall treatment plan and monitoring requirements. Regular assessment and careful monitoring are recommended to ensure optimal therapeutic outcomes in this population.

Pregnancy

Animal reproduction studies have not been conducted with topical phenylephrine. Therefore, it is not known whether phenylephrine can cause fetal harm when administered to a pregnant woman or affect reproductive capacity. Given the lack of data, phenylephrine hydrochloride should be administered to a pregnant woman only if clearly needed. Healthcare professionals should weigh the potential benefits against any unknown risks when considering the use of this medication in pregnant patients.

Lactation

It is not known whether phenylephrine hydrochloride ophthalmic solution 2.5% and 10% is excreted in human breast milk. Due to the potential for many drugs to be excreted in human milk, caution should be exercised when administering this medication to lactating mothers. Healthcare professionals should consider the risks and benefits of treatment in nursing women, particularly in relation to the possible effects on breastfed infants.

Renal Impairment

Patients with renal impairment may not have specific information regarding dosage adjustments, special monitoring, or safety considerations outlined in the prescribing information. Therefore, healthcare professionals should exercise caution when prescribing this medication to patients with reduced kidney function, as the absence of detailed guidance necessitates careful clinical judgment and individualized patient assessment. Regular monitoring of renal function is advisable to ensure patient safety and therapeutic efficacy.

Hepatic Impairment

Patients with hepatic impairment have not been specifically studied in relation to the use of this medication. Consequently, there are no established dosage adjustments, special monitoring requirements, or precautions for individuals with compromised liver function. It is recommended that healthcare providers exercise caution when prescribing this medication to patients with hepatic impairment, given the lack of data on its safety and efficacy in this population. Regular monitoring of liver function may be prudent in these cases, although specific parameters are not defined in the available information.

Overdosage

Overdosage of phenylephrine can lead to significant cardiovascular and neurological effects. A notable consequence of overdosage is a rapid increase in blood pressure, which may pose serious health risks to the patient.

In addition to hypertension, symptoms may include headache, anxiety, nausea, vomiting, and the potential for ventricular arrhythmias. These manifestations require immediate attention to mitigate further complications.

Management of phenylephrine overdosage should involve the prompt administration of a rapidly acting alpha-adrenergic blocking agent, such as phentolamine. This intervention is crucial in reversing the hypertensive effects and stabilizing the patient's condition. Healthcare professionals are advised to monitor the patient closely for any evolving symptoms and to provide supportive care as necessary.

Nonclinical Toxicology

Animal reproduction studies have not been conducted with topical phenylephrine. The potential for phenylephrine to cause fetal harm when administered to a pregnant woman or to affect reproductive capacity is not known. Therefore, phenylephrine hydrochloride should be administered to a pregnant woman only if clearly needed.

No specific non-teratogenic effects or additional nonclinical toxicology details have been identified in the available data. Furthermore, there are no specific findings related to animal pharmacology and toxicology.

Postmarketing Experience

Serious cardiovascular reactions have been reported with the use of the 10% strength formulation, including ventricular arrhythmias, some of which have been fatal. It is recommended to monitor blood pressure in patients with pre-existing cardiovascular disease. Significant elevations in blood pressure have also been noted, particularly in pediatric patients under 5 years of age, as well as in individuals with cardiovascular disease or hyperthyroidism. For patients at high risk, blood pressure should be monitored following treatment.

Rebound miosis has been documented occurring one day after instillation. Ocular adverse reactions reported include eye pain, stinging upon instillation, temporary blurred vision, and photophobia.

Cardiovascular adverse reactions encompass increases in blood pressure, syncope, myocardial infarction, tachycardia, arrhythmia, and subarachnoid hemorrhage. A marked increase in blood pressure has been particularly noted in low weight premature neonates, infants, and hypertensive patients. The cardiovascular effects have primarily been observed in hypertensive patients following the topical ocular use of phenylephrine hydrochloride ophthalmic solution 10%, with similar adverse events reported.

Patient Counseling

Healthcare providers should advise patients not to touch the dropper tip to any surface, as this may lead to contamination of the solution. It is important for patients to understand that maintaining the integrity of the dropper is crucial for their safety and the effectiveness of the treatment.

Additionally, healthcare providers should inform patients that they may experience sensitivity to light, particularly when their pupils are dilated. Patients should be counseled to protect their eyes in bright illumination to prevent discomfort and potential harm.

Storage and Handling

Phenylephrine Hydrochloride Ophthalmic Solution, USP is supplied in a container that must be kept tightly closed to maintain its integrity. It should be stored at a controlled room temperature of 20°C to 25°C (68°F to 77°F) and protected from light and excessive heat.

Healthcare professionals are advised to inspect the solution prior to use; it should not be used if it appears brown or contains any precipitate. Once opened, the solution can be used until the expiration date indicated on the bottle.

Additional Clinical Information

No further data are available.

FDA Insert (PDF)

This document is the official FDA-approved prescribing information for Phenylephrine Hydrochloride as submitted by Alcon Laboratories, Inc.. It includes detailed information about indications, dosage, contraindications, warnings, and clinical pharmacology.

View full prescribing information (PDF)