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Overview: Phenylephrine ophthalmic is an eye drop used to dilate the pupils and relax eye muscles before eye exams or procedures. The most common side effects are pain and stinging after placing the drop in the eye, blurry vision, and sensitivity to light. Serious side effects are rare but can include severe allergic reactions and increased blood pressure. After using phenylephrine ophthalmic, wear sunglasses to protect your eyes from bright light. And do not drive or do other activities that require clear vision until your eyes go back to normal. 

Uses

What is phenylephrine ophthalmic (eye) used for?

Phenylephrine ophthalmic is commonly used to widen the pupils (dilation) and paralyze certain eye muscles to get your eyes ready for an eye exam or procedure.

Phenylephrine ophthalmic may also be used for other conditions as determined by your health care provider.

Phenylephrine is also available in other forms. See Phenylephrine and Phenylephrine nasal for more information.

How does phenylephrine ophthalmic work (mechanism of action)?

Phenylephrine ophthalmic is a dilating eye drop. It works by blocking signals to certain eye muscles that control pupil size and focus. This dilates, or widens, the pupils and relaxes the eye muscles, temporarily stopping the eye from focusing on close objects. 

How is phenylephrine ophthalmic supplied (dosage forms)?

Brands and other names

  • Altafrin
  • Neofrin

Dosage forms and strengths

  • 2.5% ophthalmic solution (eye drops)
  • 10% ophthalmic solution (eye drops)

How should I store phenylephrine ophthalmic?

Phenylephrine ophthalmic should be stored at room temperature, between 68 F and 77 F (20 C and 25 C). Store it in a cool, dry place that is protected from light. Keep the lid tightly closed between uses.

 

Side Effects

What are the most common side effects of phenylephrine ophthalmic?

The most common side effects of phenylephrine ophthalmic are listed below. Tell your health care provider if you have any of these side effects that bother you.

  • Burning or stinging after you put the drop in your eye
  • Blurry vision
  • Sensitivity to light
  • Increased blood pressure (see below)
  • Heart problems (10% strength; see below)

There may be other side effects of phenylephrine ophthalmic that are not listed here. Contact your health care provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088 (800-332-1088). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of phenylephrine ophthalmic?

While less common, the most serious side effects of phenylephrine ophthalmic are described below, along with what to do if they happen.

Severe Allergic Reactions. Phenylephrine ophthalmic may cause allergic reactions, which can be serious. Stop using phenylephrine ophthalmic and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Increased Blood Pressure (Hypertension). Phenylephrine ophthalmic mainly works in the eye, but it may be absorbed into the blood and cause whole-body (systemic) side effects, such as increased blood pressure. This risk is higher with the 10% strength than the 2.5% strength version. The risk is also higher if phenylephrine ophthalmic is used in babies, young children, and people with heart or thyroid problems. Your health care provider may monitor your blood pressure after use. Call your health care provider if your blood pressure increases while using this medicine.

If you measure your blood pressure and the top number (systolic) is 180 mm Hg or higher or the bottom number (diastolic) is 120 mm Hg or higher, get medical attention right away. Increases in blood pressure may not be noticeable, but look out for and tell your health care provider right away if you have any of the following symptoms of severely high blood pressure.

  • Loss of vision
  • Eye pain or redness
  • Sudden severe headache
  • Chest pain
  • Dizziness or confusion
  • Trouble breathing
  • Nausea or vomiting
  • New or worsening vision problems
  • Anxiety
  • Buzzing in the ears
  • Nosebleed
  • Feeling of skipped heartbeats
  • Seeing bright, colorful circles around lights (vision halos)

Heart Problems. Phenylephrine ophthalmic 10% may cause certain effects on the heart, such as raising your heart rate or blood pressure. This risk may be higher in people with heart or blood pressure problems. Serious heart rhythm problems and heart attacks have been reported in a few people who used phenylephrine ophthalmic 10%. If you measure your blood pressure and the top number (systolic) is 180 mm Hg or higher or the bottom number (diastolic) is 120 mm Hg or higher, get medical attention right away. Also call your health care provider or get medical attention right away if you have chest pain, a fast or irregular heartbeat, or if you feel your heartbeat more than usual.

Warnings & Precautions

Who should not use phenylephrine ophthalmic?

Allergies to Ingredients. People who are allergic to any of the following should not use phenylephrine ophthalmic.

  • Altafrin
  • Neofrin
  • Phenylephrine ophthalmic
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in the specific phenylephrine ophthalmic products they stock.

Heart and Thyroid Problems. Phenylephrine ophthalmic 10% should not be used in people with high blood pressure or too much thyroid hormone (thyrotoxicosis) due to the risk of side effects. In these cases, a lower strength of this medicine can be used if your health care provider prescribes it.

Infants. Phenylephrine ophthalmic 10% should not be used in babies less than 1 year old due to a higher risk of whole-body (systemic) side effects. A lower strength of this medicine can be used in this age group if your health care provider prescribes it.

What should I know about phenylephrine ophthalmic before using it?

If phenylephrine ophthalmic has been prescribed to you by a health care provider, use it as prescribed.

Do not share your bottle of phenylephrine eye drops with other people, even if they have the same condition as you. It may harm them or spread germs.

Keep phenylephrine ophthalmic out of the reach of children.

Phenylephrine ophthalmic is an eye drop medicine. Make sure that you or a caregiver understands how to properly insert eye drops. Do not use it if the phenylephrine ophthalmic is brown or has solid particles in it. If you have any questions, talk to your health care provider.

Eye infections may happen if your eye drop container gets contaminated with bacteria or other germs. In some cases, eye infections may become severe and lead to vision loss. To help prevent infections, be careful not to let the tip of the bottle touch your eye, fingers, or any other surfaces. Wash your hands before each use. 

Phenylephrine ophthalmic causes temporary blurred vision and sensitivity to light (photophobia). Wear sunglasses to protect your eyes from bright light after use. Do not drive or do other activities that require clear vision until your eyes go back to normal. 

What should I tell my health care provider before using phenylephrine ophthalmic?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know if phenylephrine ophthalmic is right for you.

In particular, make sure that you discuss any of the following.

Other Current and Past Health Conditions. Tell your health care provider if you have any of the following.

  • High blood pressure
  • Heart problems
  • Overactive thyroid

Other Medicines and Supplements. Phenylephrine ophthalmic may interact with other medicines and supplements. Before using phenylephrine ophthalmic, tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. It is not known if or how phenylephrine ophthalmic could affect pregnancy or harm an unborn baby. Tell your health care provider if you are pregnant or plan to become pregnant. They will let you know if you should use phenylephrine ophthalmic while you are pregnant or trying to get pregnant.

Breastfeeding. It is not known if phenylephrine ophthalmic passes into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed. They will let you know if you should use phenylephrine ophthalmic while breastfeeding.

Interactions

Does phenylephrine ophthalmic interact with foods or drinks?

There are no known interactions between phenylephrine ophthalmic and foods or drinks.

It is unknown if drinking alcohol will affect phenylephrine ophthalmic. 

Does phenylephrine ophthalmic interact with other medicines (drug interactions)?

Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using or recently used any of the following medicines.

  • Atropine, which is a medicine used to dry up secretions, treat certain heart conditions, and dilate the pupil of the eye
  • An inhaled anesthetic, which is a type of medicine that you breathe in to make you sleep or relax before a surgery or procedure

This may not be a complete list of medicines that can interact with phenylephrine ophthalmic. Always check with your health care provider.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much phenylephrine ophthalmic?

If you or someone else has used too much phenylephrine ophthalmic, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of phenylephrine ophthalmic?

Phenylephrine ophthalmic is usually used by a health care provider in a hospital or clinic. Your health care provider will make sure you are receiving phenylephrine ophthalmic as scheduled. 

If you use phenylephrine ophthalmic at home and you miss a scheduled dose, use it as soon as you remember. If it is almost time for the next dose, only use the next dose. Do not use double or extra doses.