Generic Name: phenylephrine (FEN-il-EF-rin)
Brand Name: Examples include Neo-Synephrine and Vazculep
Phenylephrine is used for:
Maintaining blood pressure in certain acute low blood pressure situations. It is also used to treat blood vessel failure during shock and low blood pressure or allergic reactions caused by other medications. It may also be used for other conditions as determined by your doctor.
Phenylephrine is a vasopressor. It works by constricting blood vessels and raising blood pressure.
Do NOT use phenylephrine if:
- you are allergic to any ingredient in phenylephrine
- you have severe high blood pressure
Contact your doctor or health care provider right away if any of these apply to you.
Before using phenylephrine:
Some medical conditions may interact with phenylephrine. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have a history of high blood pressure, heart problems (eg, heart failure, irregular heartbeat), blood vessel disease, chest pain (angina), spinal cord injury, kidney problems, high blood pressure in the lungs (pulmonary arterial hypertension), blood clots, asthma, liver problems, intestinal problems, diabetes, an overactive thyroid, or low blood fluid volume
Some MEDICINES MAY INTERACT with phenylephrine. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Alpha blockers (eg, doxazosin), angiotensin-converting enzyme (ACE) inhibitors (eg, lisinopril), benzodiazepines (eg, alprazolam), calcium channel blockers (eg, nifedipine), guanfacine, mixed alpha- and beta-blockers (eg, propranolol), phosphodiesterase-5 (PDE-5) inhibitors (eg, sildenafil), or reserpine because they may decrease phenylephrine's effectiveness
- Aldosterone, angiotensin, atomoxetine, atropine, corticosteroids (eg, hydrocortisone), ergot alkaloids (eg, methylergonovine), monoamine oxidase inhibitors (MAOIs) (eg, phenelzine), oxytocic medicines (eg, oxytocin), or tricyclic antidepressants (eg, amitriptyline) because they may increase the risk of phenylephrine's side effects
This may not be a complete list of all interactions that may occur. Ask your health care provider if phenylephrine may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use phenylephrine:
Use phenylephrine as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Phenylephrine is administered as an injection at your doctor's office, hospital, or clinic. Contact your health care provider if you have any questions.
- Call your doctor to find out what to do.
Ask your health care provider any questions you may have about how to use phenylephrine.
Important safety information:
- Some of these products contain sulfites, which can cause allergic reactions in certain individuals (eg, asthma patients). If you have previously had allergic reactions to sulfites, contact your pharmacist to determine if the product you are taking contains sulfites.
- Phenylephrine may cause tissue damage if it leaks from the vein. Tell your nurse if you have any redness, burning, pain, swelling, blisters, skin sores, or leaking of fluid where the medicine is going into your body.
- Tell your doctor or dentist that you take phenylephrine before you receive any medical or dental care, emergency care, or surgery.
- Have your blood pressure checked often. Talk with your doctor.
- Lab tests, including kidney function, may be performed to while you use phenylephrine. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
- Use phenylephrine with caution in the ELDERLY; they may be more sensitive to its effects.
- PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using phenylephrine while you are pregnant. It is unknown if phenylephrine is found in breast milk. If you are or will be breast-feeding while you use phenylephrine, check with your doctor. Discuss any possible risks to your baby.
Possible side effects of phenylephrine:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Dizziness; excitability; headache; nausea; restlessness; sweating a lot; trouble sleeping; vomiting.
Severe allergic reactions (rash; hives; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); blurred vision; chest pain; severe headache or dizziness; shakiness; shortness of breath, a big weight gain, or swelling in the arms or legs; slow or irregular heartbeat; tingling or numbness in the hands or feet.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.Proper storage of phenylephrine:
Phenylephrine is handled and stored by a health care provider. You will not store it at home. Keep all medicines, as well as needles and syringes, out of the reach of children and away from pets.
- If you have any questions about phenylephrine, please talk with your doctor, pharmacist, or other health care provider.
- Phenylephrine is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information should not be used to decide whether or not to take phenylephrine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about phenylephrine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to phenylephrine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using phenylephrine.
Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.
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