Neo-Synephrine Side Effects Center

Last updated on RxList: 7/14/2022
Neo-Synephrine Side Effects Center

What Is Neo-Synephrine?

Neo-Synephrine (phenylephrine hydrochloride ophthalmic solution) is a vasoconstrictor (constricts the veins) and mydriatic (dilates the pupils), and the over-the-counter strength is used to relieve redness, burning, irritation, and dryness of the eye caused by wind, sun, and other minor irritants. Prescription-strength Neo-Synephrine is used to constrict blood vessels in the eye and to dilate (make bigger) the pupil for conditions such as glaucoma, before surgery, and before eye examinations. Neo-Synephrine is available in generic form.

What Are Side Effects of Neo-Synephrine?

Common side effects of Neo-Synephrine include:

  • burning,
  • stinging,
  • pain,
  • increased redness of the eye,
  • tearing or blurred vision,
  • headache,
  • tremor,
  • nausea,
  • sweating,
  • nervousness,
  • dizziness,
  • drowsiness,
  • dryness in the nose,
  • runny nose, and
  • sneezing

Seek medical care or call 911 at once if you have the following serious side effects:

  • Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
  • Serious heart symptoms such as fast, irregular, or pounding heartbeats; fluttering in your chest; shortness of breath; and sudden dizziness, lightheartedness, or passing out;
  • Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, loss of coordination, feeling unsteady, very stiff muscles, high fever, profuse sweating, or tremors.

This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.

Dosage for Neo-Synephrine

The dose of Neo-Synephrine depends on the condition being treated.

What Drugs, Substances, or Supplements Interact with Neo-Synephrine?

Neo-Synephrine may interact with monoamine oxidase inhibitors (MAOIs) or beta-blockers. Talk to your doctor before taking any prescription or over-the-counter medicines, including vitamins, minerals, and herbal products.

Neo-Synephrine During Pregnancy or Breastfeeding

It is not known whether Neo-Synephrine will be harmful to a fetus. Talk to your doctor if you are pregnant or could become pregnant during treatment. It is not known whether this medication passes into breast milk. Consult your doctor before breastfeeding.

Additional Information

Our Neo-Synephrine (phenylephrine hydrochloride ophthalmic solution) Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


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Neo-Synephrine Consumer Information

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Although the risk of serious side effects is low when phenylephrine ophthalmic is used in the eyes, side effects can occur if the medicine is absorbed into your bloodstream. Stop using phenylephrine ophthalmic and call your doctor at once if you have:

  • fast or irregular heart rate;
  • sweating, tremors;
  • pale skin, light-headed feeling;
  • severe headache, buzzing in your ears, anxiety, shortness of breath; or
  • chest pain or pressure, pain spreading to your jaw or shoulder.

Less serious side effects may be more likely, and you may have none at all.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


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Neo-Synephrine Professional Information


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Read the entire FDA prescribing information for Neo-Synephrine (Phenylephrine Hydrochloride Ophthalmic Solution)


In the U.S., 1 in every 4 deaths is caused by heart disease. See Answer

© Neo-Synephrine Patient Information is supplied by Cerner Multum, Inc. and Neo-Synephrine Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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