TAVEGYL 1MG TABLET

Indications

• Allergic rhinitis
• Allergic conjunctivitis
• Urticaria
• Pruritus associated with allergic conditions
• Insomnia (off-label use)

Dosage

Children: Refer to the appropriate clinical guidelines or BNF for specific dosing recommendations.

Adults: Refer to the appropriate clinical guidelines or BNF for specific dosing recommendations.

Mechanism of action

Clemestine exerts its antihistaminic effect by competitively inhibiting the binding of histamine to the H1 receptor. This blockade prevents the physiological effects of histamine, which include vasodilation, increased vascular permeability, and stimulation of sensory nerves. Additionally, clemestine may have anticholinergic effects, contributing to its sedative properties.

Pharmacodynamics

The pharmacodynamics of clemestine involve a reduction in the effects of histamine on target tissues, leading to decreased vascular permeability and relief from symptoms such as itching, swelling, and redness. The sedative effects can also impact the central nervous system, making the drug useful in situations requiring both antihistaminic and calming effects.

Pharmacokinetics

Clemestine is well-absorbed after oral administration, with peak plasma concentrations typically occurring within 2 to 3 hours. It has a relatively long half-life, allowing for once or twice daily dosing in many cases. The drug is metabolized in the liver and excreted through the kidneys. The onset of action usually occurs within 1 hour, and effects can last for up to 12 hours.

Contra-indications

• Hypersensitivity to clemastine or any other component of the formulation
• Severe urinary retention
• Angle-closure glaucoma
• Severe asthma exacerbation

Adverse effects

• Drowsiness
• Dry mouth
• Dizziness
• Blurred vision
• Constipation
• Urinary retention

Interactions

• Increased sedation with alcohol and central nervous system depressants
• Anticholinergic effects may be enhanced when used with other anticholinergic drugs
• May reduce the effectiveness of some antihypertensive medications

Precautions

• Use with caution in patients with a history of seizures
• Caution in elderly patients due to increased sensitivity to side effects
• Caution in patients with cardiovascular diseases due to potential tachycardia
• Assess for potential interactions with other medications

Pregnancy

Clemastine is categorized as a Category B drug. Animal studies have not demonstrated any harm, but there are insufficient studies in pregnant women. It should be used only if clearly needed.

Breast-feeding

Clemastine is excreted in breast milk. Caution is advised when administered to nursing mothers, as it may affect the infant.

Storage

Store at room temperature, away from moisture and heat. Do not freeze.

Formulations

• Tablets
• Syrup
• Injectable solution