The possible side effects (hazards) of antihistamines taken for a long period of time are drowsiness, weight gain, and induction of allergic reactions.
1. Drowsiness: Generation 1 antihistamines should not be taken for a long period of time because the ingredients in them can interfere with fast-moving eye sleep, affecting the patient’s learning and cognitive-behavioral abilities.
2. Weight gain: some of the second generation of antihistamines, such as astemizole and azelastine, due to the inhibition of pyloric H1 receptors, will accelerate gastric emptying, gastric emptying after people will have a feeling of hunger, long-term stimulation of appetite, excessive diet will lead to weight gain.
3. Metabolic reaction: antihistamines are used to treat metabolic diseases, but they can also cause metabolic reactions, mainly in the skin, such as drug dermatitis, and in severe cases, allergic shock can occur. For patients with allergic shock should immediately use epinephrine and other rescue measures. Patients with skin rash should stop the drug and change to other drugs or methods.
Antihistamine drugs should not be taken for a long time, the specific treatment course should also be used under the guidance of a professional physician, and should not be used and discontinued without authorization.