Methdilazine

Methdilazine is a first-generation antihistamine of the phenothiazine class. It is used primarily for the treatment of hay fever, rhinitis, urticaria, and asthma. Methdilazine works by blocking the effects of histamine, a substance in the body that causes allergic symptoms.

Pharmacology

Methdilazine is a competitive H1 receptor antagonist, meaning it blocks the action of histamine at the H1 receptor. This prevents histamine from causing allergic symptoms such as itching, sneezing, and runny nose. Methdilazine also has anticholinergic effects, which can help to reduce nasal congestion.

Clinical Use

Methdilazine is used to treat a variety of allergic conditions, including hay fever, rhinitis, urticaria, and asthma. It can also be used to treat allergic conjunctivitis, dermatitis, and angioedema. Methdilazine is typically taken orally, either as a tablet or liquid.

Side Effects

Like other first-generation antihistamines, Methdilazine can cause a number of side effects. These can include drowsiness, dry mouth, blurred vision, and constipation. In rare cases, Methdilazine can cause more serious side effects such as confusion, hallucinations, and seizures.

Contraindications

Methdilazine should not be used in patients with a known hypersensitivity to phenothiazines. It should also be used with caution in patients with glaucoma, prostate enlargement, or urinary retention.

See Also

• Antihistamine
• Phenothiazine
• Histamine
• H1 receptor