Cinnarizine + Dimenhydrinate
Indications
Cinnarizine + Dimenhydrinate is used for:
Nausea and vomiting, motion sickness, vertigo, meniere's disease, peripheral vascular diseases, cerebrovascular disorders, vestibular disorders
Adult Dose
Oral
Peripheral vascular disease
Adult: 75 mg bid or tid.
Motion sickness
Adult: 30 mg 2 hr before travel then 15 mg 8 hrly during the journey if necessary.
Cerebrovascular disorders
Adult: 75 mg once daily.
Vertigo and vestibular disorders
Adult: 30 mg tid or 75 mg 1-2 times daily.
Child Dose
Oral
Motion sickness
Child: 5-12 yr 15 mg 2 hr before travel then 7.5 mg 8 hrly during the journey as necessary.
Vertigo and vestibular disorders
Child: 5-12 yr 15 mg tid.
Renal Dose
Administration
Should be taken with food.
Contra Indications
Proven hypersensitivity to the drug. Parkinson's disease. Childn and neonates.
Precautions
Hypotension; pregnancy; lactation; elderly. May impair ability to drive or operate machineries.
Pregnancy-Lactation
Interactions
Cinnarizine: CNS depressant effect enhanced with alcohol. Action potentiated by domperidone.
Dimenhydrinate: Physically incompatible with aminophylline, hydrocortisone, phenothiazines and some barbiturates in solution.
Potentially Fatal: Potentiates the sedative effects of CNS depressants including alcohol, barbiturates, opioid analgesics, sedatives and neuroleptics. MAOIs, atropine, TCAs enhance antimuscarinic effect. Masks ototoxicity produced by aminoglycoside antibiotics.
Adverse Effects
Side effects of Cinnarizine + Dimenhydrinate :
Extrapyramidal symptoms sometimes associated with severe depression. Drowsiness, headache, GI upsets, unsteadiness, headache; rarely skin and hypersensitivity reactions, dry mouth, blurred vision, urinary difficulty or retention, constipation and increased gastric reflux, fatigue. Hypolipidaemic effect.
Mechanism of Action
Cinnarizine has calcium-channel blocking activity selective for arterial smooth muscle. It also has some antihistamine activity. Cinnarizine acts as a labyrinthine sedative. It also improves microcirculation by reducing ischaemia-induced blood viscosity.
Dimenhydrinate is an antihistamine which also has antimuscarinic and central sedative action. It also exerts a depressant action on hyperstimulated labyrinthine function.