Type of medicine Antihistamine
Used for Allergies, sometimes migraine and other types of headache
Also called Periactin
Available as Tablets

Periactin is used to prevent and relieve allergic conditions such as hay fever and some allergic skin reactions.

Exposure to pollen, pet fur, house dust or an insect bite can cause the body to produce a chemical called histamine. The release of histamine causes allergic symptoms which can include rashes, sneezing, watery eyes and a running or blocked nose. Antihistamines stop the effects of histamine and help to relieve these symptoms.

Periactin is also occasionally used to prevent migraines.

Why is this drug prescribed?

Cyproheptadine belongs to a group of drugs called antihistamines. Histamine is released when the body responds to an allergen e.g. pollen, cat hair, bird feathers. It binds to receptors causing a range of effects, including, widening of small blood vessels in the nose and eyes and contraction of the muscles of the gastro-intestinal and respiratory tracts. These effects are responsible for the characteristic symptoms of allergies. Cyproheptadine blocks the action of histamine on H1 receptors, thereby relieving the symptoms of allergic reactions. Cyproheptadine is also used in the prevention or treatment of migraine headaches. It is not fully understood how it works in this condition. In addition to blocking the actions of histamine, it blocks the action of a chemical in the brain called serotonin. These chemicals are involved in migraine. Cyproheptadine is called a sedating anti-histamine as it enters the brain in significant quantities and is therefore more likely to cause drowsiness than the newer group of non-sedating anti-histamines.

Treatments

* Follow-up treatment for a severe allergic reaction * Migraine * Sudden or ongoing conditions caused by allergy * Sudden or ongoing conditions causing itch

What side effects can this drug cause?

* Blurred vision * Difficulty in passing urine * Dry mouth * Drowsiness * Confusion * Blood disorders * Disturbances of the gut such as diarrhoea, constipation, nausea, vomiting or abdominal pain * Awareness of your heart beat * Low blood pressure * Dizziness * Sleepiness * Irritability * Wheezing or difficulty in breathing