Medical Editor: Melissa Conrad Stöppler, MD
Phenergan (promethazine HCI) is an antihistamine used to treat nausea and vomiting related to certain conditions (e.g., motion sickness, before/after surgery). Phenergan is also used to treat allergic symptoms such as rash, itching, and runny nose. The brand name Phenergan is discontinued in the U.S. Phenergan is available as a generic drug. Common side effects of Phenergan (promethazine HCI) include
- blurred vision,
- dry mouth,
- stuffy nose,
- ringing in your ears,
- weight gain,
- swelling in your hands or feet,
- trouble having an orgasm, or
The dose of Phenergan to treat allergies is 25 mg taken before retiring. The adult dose of Phenergan to treat motion sickness is 25 mg taken twice daily. The dose of Phenergan for the active therapy of nausea and vomiting in children or adults is 25 mg. Phenergan may interact with cold or allergy medicine, sedatives, narcotics, sleeping pills, muscle relaxers, seizure medications, antidepressants, anxiety medicines, lithium, atropine, belladonna, benztropine, dimenhydrinate, methscopolamine, scopolamine, blood pressure medications, blood thinners, bronchodilators, bladder or urinary medications, MAO inhibitors, medicines to treat Parkinson's disease, restless leg syndrome medications, medicines to treat pituitary gland tumor, or medicines to treat stomach ulcer or irritable bowel syndrome. Tell your doctor all medications and supplements you use. Phenergan Tablets and Suppositories should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. It is not known whether Phenergan is excreted in human milk. Because of the potential for serious adverse reactions in nursing infants from Phenergan Tablets and Suppositories, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
Our Phenergan 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.
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Stop using promethazine and call your doctor at once if you have any of these serious side effects:
- twitching, or uncontrollable movements of your eyes, lips, tongue, face, arms, or legs;
- tremor (uncontrolled shaking), drooling, trouble swallowing, problems with balance or walking;
- feeling restless, jittery, or agitated;
- high fever, stiff muscles, confusion, sweating, fast or uneven heartbeats, rapid breathing;
- feeling like you might pass out;
- seizure (convulsions);
- pale skin, easy bruising or bleeding, fever, sore throat, flu symptoms;
- decreased night vision, tunnel vision, watery eyes, increased sensitivity to light;
- hallucinations, agitation;
- nausea and stomach pain, skin rash, and jaundice (yellowing of the skin or eyes);
- urinating less than usual or not at all;
- joint pain or swelling with fever, swollen glands, muscle aches, chest pain, vomiting, unusual thoughts or behavior, and patchy skin color; or
- slow heart rate, weak pulse, fainting, slow breathing (breathing may stop).
Less serious side effects may include:
- dizziness, drowsiness, anxiety;
- blurred vision, dry mouth, stuffy nose;
- ringing in your ears;
- weight gain, swelling in your hands or feet;
- impotence, trouble having an orgasm; or
This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.
Read the entire detailed patient monograph for Phenergan (Promethazine)
Central Nervous System
Drowsiness is the most prominent CNS effect of this drug. Sedation, somnolence, blurred vision, dizziness; confusion, disorientation, and extrapyramidal symptoms such as oculogyric crisis, torticollis, and tongue protrusion; lassitude, tinnitus, incoordination, fatigue, euphoria, nervousness, diplopia, insomnia, tremors, convulsive seizures, excitation, catatonic-like states, hysteria. Hallucinations have also been reported.
Hyperexcitability and abnormal movements have been reported in patients following a single administration of promethazine HCl. Consideration should be given to the discontinuation of promethazine HCl and to the use of other drugs if these reactions occur. Respiratory depression, nightmares, delirium, and agitated behavior have also been reported in some of these patients.
To report SUSPECTED ADVERSE REACTIONS, contact Renaissance Pharma, Inc. at 1-866-897-5002 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
Read the entire FDA prescribing information for Phenergan (Promethazine)
© Phenergan Patient Information is supplied by Cerner Multum, Inc. and Phenergan Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.