Chlorpheniramine is an antihistamine that works by blocking the effects of histamine in the brain. Histamine is a chemical that is naturally found in the body and is involved in a number of functions, including allergic reactions, inflammation, and wakefulness.
When chlorpheniramine blocks histamine, it can have several effects on the brain:
- Reduces allergic reactions: By blocking histamine, chlorpheniramine can help to reduce the symptoms of allergies, such as sneezing, runny nose, and itchy eyes.
- Causes drowsiness: Chlorpheniramine can cross the blood-brain barrier and enter the central nervous system, where it can cause drowsiness. This is because it can interfere with the brain's natural wakefulness signals.
- May improve sleep: While not specifically designed as a sleep aid, the drowsiness caused by chlorpheniramine can sometimes help people fall asleep easier.
It is important to note that chlorpheniramine is not a cure for allergies. It simply helps to manage the symptoms. It is also important to use chlorpheniramine as directed by a doctor or pharmacist, as it can interact with other medications and have side effects.