Pheniramine is a first generation antihistamine that provides allergy relief. It is used to treat allergic reactions such as hay fever and runny nose, skin rashes and itching. There are only a few single drug preparations containing pheniramine. Many products, however, contain it in combination with a decongestant and/or analgesic for colds and flu.
Antihistamines such as pheniramine are an allergy treatment that work by blocking histamine in the body. Histamine is released by the immune system when it detects anything foreign in the body. It causes the blood vessels to dilate, allowing the white cells to flow freely to the infected area, to fight the infection. This causes inflammation and redness.
In the case of hay fever, the body mistakenly identifies an allergen, such as pollen, as a potential danger, thus triggering histamine release. The result is a blocked, stuffy or runny nose and red, watery eyes. In some more severe allergic reactions, the lungs may be affected, causing narrowing of the airways and wheezing. In the case of anaphylaxis, the airway may block completely. This is a medical emergency and requires immediate medical intervention.
By blocking the release of histamine, antihistamines like pheniramine stop this cascade of actions. Many people who suffer from chronic seasonal allergies take antihistamines throughout the pollen season, thus preventing hay fever. Those allergic to other allergens such as cats or shellfish may carry an antihistamine with them, in the case of inadvertent contact. It is advised that people with such allergies wear a bracelet or tag detailing their allergy, in case of an emergency.
Pheniramine is not only antihistaminic but has also anticholinergic properties. It is these properties that are the main cause of the possible side effects of this allergy treatment. The most common side effect is drowsiness, and people taking the drug should not drive or operate heavy machinery. Other possible side effects include dryness of the mouth, nose or throat and difficulty urinating.
In some countries pheniramine and pheniramine-containing products are available over the counter, whereas in others a prescription may be required. Before using this medicine, medical history and current or future conditions such as pregnancy should be discussed with a doctor first. Pheniramine may interact with other medications, including homeopathic and complementary medicines. Additive side effects should also be considered, especially if pheniramine is used with other medications that could cause central nervous system depression or drowsiness.