Phenylephrine (patient information)
Why this medication is prescribed
Phenylephrine is used to relieve nasal discomfort caused by colds, allergies, and hay fever. It is also used to relieve sinus congestion and pressure. Phenylephrine is in a class of medications called nasal decongestants. It works by reducing swelling of the nasal passages.
How this medication should be used
Phenylephrine comes as a tablet to take by mouth. It is usually taken every 4 hours as needed. Do not take more than 6 doses in a 24-hour period. Follow the directions on the package label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take phenylephrine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Your symptoms should improve during your treatment. If your symptoms do not get better within 7 days or if you have a fever, stop taking phenylephrine and call your doctor.
Other uses for this medicine
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
Special precautions
Before taking phenylephrine:
- tell your doctor and pharmacist if you are allergic to phenylephrine or any other medications.
- do not take phenylephrine if you are taking monoamine oxidase (MAO) inhibitors, including isocarboxazid (Marplan), phenelzine (Nardil), selegiline (Eldepryl), and tranylcypromine (Parnate), or have stopped taking them within the past 2 weeks.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. You should know that phenylephrine may in used in combination with other medications to treat colds, allergies, and sinus headaches. Be sure to read the information provided for the patient when taking combination products to be sure that you are not taking additional medications that contain the same ingredient.
- tell your doctor if you have or have ever had high blood pressure, diabetes, trouble urinating because of an enlarged prostate gland, or thyroid or heart disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking phenylephrine, call your doctor.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking phenylephrine.
Special dietary instructions
Unless your doctor tells you otherwise, continue your normal diet.
What to do if you forget a dose
This medication is usually taken as needed. If your doctor has told you to take phenylephrine regularly, take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
Side Effects
Minor Side Effects
Phenylephrine may cause side effects. Some side effects can be serious. If you experience any of these symptoms, stop using phenylephrine and call your doctor immediately:
- nervousness
- dizziness
- sleeplessness
Phenylephrine may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at http://www.fda.gov/MedWatch/report.htm] or by phone [1-800-332-1088].
Storage conditions needed for this medication
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
In case of emergency/overdose
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Other information
Ask your pharmacist any questions you have about phenylephrine.
Brand names
- Sudafed PE®