Phenylephrine (injection)

Phenylephrine is used to increase blood pressure in adults who have life-threatening low blood pressure due to septic shock or from anesthesia during a surgery or procedure.

Phenylephrine may also be used for reasons not mentioned in this medication guide.

Phenylephrine is given through an injection into a vein by a healthcare provider.

You will need regular medical tests. Your heart rate and blood pressure will be monitored continuously, and your kidney function may need to be checked frequently.

Let your medical caregivers know if you feel any burning or pain during the injection of phenylephrine.

Use only as directed. Inform your doctor if you are taking other medicines or have any other medical conditions or allergies.

You should not be treated with phenylephrine if you are allergic to it.

Tell your doctor if you have or have ever had:

• heart problems including chest pain or coronary artery disease (clogged arteries);
• pulmonary arterial hypertension;
• blood circulation problems;
• a history of a condition called autonomic dysfunction (as can occur with spinal cord injury);
• asthma or sulfite allergy;
• if you use a medicine that stimulates contractions of the uterus in a woman;
• fluid in the lungs; or
• liver or kidney disease.

It is not known if phenylephrine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Ask a doctor if it is safe to breastfeed while using phenylephrine.

In an emergency, you may not be able to tell your medical caregivers about your medical conditions or if you are pregnant or breastfeeding. Make sure any follow-up doctor knows you received this medicine.

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

Tell your medical caregivers right away if you have:

• pale skin, severe shortness of breath, wheezing, cough with foamy mucus;
• fast, slow, or uneven heart rate;
• severe headache, blurred vision, pounding in your neck or ears;
• chest pain or pressure, pain spreading to your jaw or shoulder, nausea;
• pain, burning, irritation, or skin changes where the injection was given;
• numbness, tingling, burning pain in your hands or feet;
• dizziness;
• tremors;
• sweating or flushing (sudden warmth, redness, or tingly feeling); or
• kidney problems—swelling, urinating less, feeling tired or short of breath.

Common side effects of phenylephrine may include:

• headache;
• feeling nervous or excited; or
• nausea or vomiting.

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.

Usual Adult Dose for Hypotension:

Perioperative dosing (patients undergoing surgery with neuraxial or general anesthesia):Initial dose: 50 to 250 mcg by intravenous bolus (most common doses: 50 to 100 mcg)Maintenance dose: 0.5 to 1.4 mcg/kg/min by intravenous continuous infusion (titrate to blood pressure goal)Septic or Other Vasodilatory Shock:0.5 to 6 mcg/kg/min by intravenous continuous infusion (titrate to blood pressure goal)-No bolus-Doses over 6 mcg/kg/min do not show significant incremental blood pressure increases.

Usual Adult Dose for Shock:

Perioperative dosing (patients undergoing surgery with neuraxial or general anesthesia):Initial dose: 50 to 250 mcg by intravenous bolus (most common doses: 50 to 100 mcg)Maintenance dose: 0.5 to 1.4 mcg/kg/min by intravenous continuous infusion (titrate to blood pressure goal)Septic or Other Vasodilatory Shock:0.5 to 6 mcg/kg/min by intravenous continuous infusion (titrate to blood pressure goal)-No bolus-Doses over 6 mcg/kg/min do not show significant incremental blood pressure increases.

Usual Adult Dose for Nasal Congestion:

10 mg orally every 4 hoursMaximum dose: 60 mg per 24 hours

Usual Pediatric Dose for Nasal Congestion:

12 years and older: 10 mg orally every 4 hoursMaximum dose: 60 mg per 24 hours

In an emergency medical setting, it is unlikely that you will miss a dose.

In a medical setting, an overdose would be handled promptly.

Follow your doctor's instructions regarding any limits on food, drinks, or activities.

Many drugs can interact with phenylephrine. This includes both prescription and over-the-counter medicines, vitamins, and herbal products. Not every possible interaction is listed here. Inform your doctor about all other medicines you are taking.