Pheniramine is an antihistamine medication that belongs to a class of drugs called first-generation H1-receptor antagonists. It is used to relieve symptoms of allergic conditions such as hay fever and allergic rhinitis, as well as to treat symptoms of the common cold such as runny nose, sneezing, and itchiness. It also used to prevent motion sickness and to alleviate symptoms of parkinsonism, a group of symptoms that resemble those of Parkinson’s disease.

Common side effects of pheniramine include:

  • Drowsiness

  • Dry mouth

  • Dizziness

  • Blurred vision

  • Constipation

  • Nausea

  • Stomach upset

Less common but serious side effects include:

  • Allergic reactions such as hives, rash, or difficulty breathing

  • Seizures

  • Increased pressure in the eyes

  • Yellowing of the skin or eyes (jaundice)

  • Unusual tiredness or weakness

  • Stomach pain, dark urine, and yellowing of the eyes or skin can be signs of liver problems.

It is important to consult with a healthcare provider if you experience any of these serious side effects while taking pheniramine. They will advise you on what to do next. Also, because it can cause drowsiness, it’s advised to avoid driving or operating heavy machinery while taking this medication and until you know how it will affect you.