BRAND NAMES
 MECHANISM OF ACTION
Dimenhydrinate, an anti-nauseant/antimemetic is the 8-Chlorotheophylline salt of diphenhydramine. 8-Chlorotheophylline, a mild central nervous system stimulants was added in order to counteract drowsiness.
Dimenhydrinate acts as antihistamine (H1-antagonist) with anticholinergic (antimuscarinic), exerting parasympatholytic and centrally-depressant effects. its antiemetic and antivertiginous effects may be related to the central anticholinergic actions on the central vestibular system: Dimenhydrinate diminish vestibular stimulation and depress labyrinthine function.
- Prevention and treatment of nausea vomiting and dizziness associated with all types of motion sickness including carsickness and seasickness
- Vertigo due to labyrinthine disorders
- Motion sickness (Tablets):
- Adults and children 12 years and over: 50 to 100 mg every 4-6 hours; maximum dosage: 400 mg in 24 hours
- Children 6-12 years: 25-50 mg every 6-8 hours; maximum dosage: 150 mg in 24 hours
- Children 2 to under 6 years: 25 mg tablet every 6-8 hours; maximum dosage: 75 mg in 24 hours.
To prevent motion sickness, the first dose should be taken ½ to 1 hour before starting activity
- Hypersensitivity to Dimenhydrinate or to diphenhydramine
- Children under the age of two years
 WARNINGS AND PRECAUTIONS
- Patients using Dimenhydrinate should be cautioned against operating automobiles or machinery requiring alertness because of the possiblility of drowsiness associated with its use.
- Avoid alcoholic beverages.
- Patients with glaucoma (use with caution)
- Urine retention due to an enlargement of the prostate gland (use with caution)
- Breathing problem such as asthma, emphysema or chronic bronchitis (use with caution)
- The effects of hypnotic, sedative and tranquilizing drugs may be synergistic if given concomitantly
 PREGNANCY AND LACTATION
- Pregnancy Category B (US). Dimenhydrinate should be used during pregnancy only if clearly needed
 SIDE EFFECTS
Drowsiness is the most common. Dizziness may also occur. Symptoms of dry mouth, fatigue, excitement and nausea have been reported.
 RELATED LINKS
|5-HT3 receptor antagonists||Dolasetron • Granisetron • Ondansetron • Palonosetron • Tropisetron|
|Dopamine antagonists||Alizapride • Bromopride • Clebopride • Domperidone • Metoclopramide • Prochlorperazine • Thiethylperazine|
|H1 antagonists||Dimenhydrinate • Meclizine|
|NK1 receptor antagonists||Aprepitant • Fosaprepitant • Maropitant|
|Motion sickness||Cinnarizine • Dimenhydrinate • Meclizine • Meclizine/Pyridoxine • Scopolamine (Patch)|
|Pregnancy||Meclizine/Pyridoxine • Ondansetron|