Buy Clemastine (meclastin) Cas 15686-51-8

Clemastine, also known as meclastin, is a first-generation H1 histamine antagonist (antihistamine) with anticholinergic properties (drying) and sedative side effects.^[1] Like all first-generation antihistamines, it is sedating.^[2][3]

Patented in 1960, it came into medical use in 1967.^[4]

Clemastine is used to relieve hay fever and allergy symptoms, including sneezing; runny nose; and red, itchy, tearing eyes. Prescription strength clemastine is also used to relieve the itching and swelling of hives.^[5]

Overdosage symptoms are paradoxical, ranging from CNS depression to stimulation. Stimulation is most common in children, and is usually followed by excitement, hallucinations, ataxia, loss of coordination, muscle twitching, athetosis, hyperthermia, cyanosis, convulsions, tremors, and hyperreflexia. This may be followed by postictal depression and cardiovascular/respiratory arrest. Other common overdose symptoms include dry mouth, fixed dilated pupils, flushing of the face, and pyrexia. In adults, overdose usually leads to CNS depression, ranging from drowsiness to coma.^[6]

Continuous and/or cumulative use of anticholinergic medications, including first-generation antihistamines, is associated with higher risk of cognitive decline and dementia in older people.^[7][8]

Clemastine is an antihistamine with anticholinergic and sedative effects. Antihistamines competitively bind to histamine receptor sites, thus reducing the neurotransmitter’s effects.^[9] Effects of histamine (which are countered by antihistamines) include:

• Increased capillary permeability
• Increased capillary dilatation
• Edema (i.e., swelling)
• Pruritus (Itch)
• Gastrointestinal/respiratory smooth muscle constriction