Patient Information on Phenergan

Phenergan, also prescribed as promethazine and Phen-Tuss, is an oral medication. It has several uses and is only available by prescription. It is important that this medication be used exactly as directed to help avoid potentially dangerous effects and interactions.

How this medication is taken depends on what it is being taken for. When taken for motion sickness, the patient should take it 30-60 minutes prior to traveling and it can be repeated every 8-12 hours if needed. This medication is taken before bedtime when taken for allergies. When taken for surgery, it is either administered just before and after surgery or the night before.

The most common side effects of Phenergan include drowsiness, constipation, dry mouth, dizziness, and blurred vision. Some patients may experience excitability instead of drowsiness. The serious side effects include lack of coordination, vision changes, severe dizziness, weakness, ringing ears, painful urination, fainting, decreased urination, slow heartbeat, shaking, mental changes, restlessness, mood changes, and involuntary movements. The very serious side effects include slow breathing, increased sweating, shallow breathing, irregular heartbeat, signs of infection, fast heartbeat, severe abdominal pain, seizures, persistent vomiting, very high fever, persistent nausea, severe muscle stiffness, bleeding easily, dark urine, bruising easily, yellow eyes, and yellow skin.

Patients taking certain other medications may have to avoid this medication to avoid drug interactions. These include epinephrine for hypotension, sibutramine, metrizamide, cough medicine, anticholinergics, cold medicine, tricyclic antidepressants, cancer chemotherapy, tramadol, guanethidine, theophylline, guanadrel, phenothiazines, other antihistamines, MAO inhibitors, medications that may increase a patient's seizure risk, isoniazid, bupropion, anti-seizure drugs, psychiatric medications, sleep medications, narcotic pain killers, anti-anxiety drugs, and muscle relaxers.

This medication should not be taken by children that are two years of age or younger. If it is taken by children of this age, they may experience potentially fatal respiratory depression, even in normal doses. Pregnant women should use extreme caution with this medication, as should those who are breastfeeding.

RxList. (2010). Phenergan. Retrieved on January 16, 2010 from RxList: http://www.rxlist.com/phenergan-drug.htm