by Richard Daub
Dramamine is one of the brand names of dimenhydrinate, an over-the-counter drug that is used to treat and prevent the dizziness, nausea, and vomiting that results from motion sickness. Besides Dramamine, it is also sold under the brand names Gravol, Vertirosan, Gravamin, and TripTone. The drug is most commonly administered in the form of a pill, but it is also available in the form of liquid, and, for severe cases of vomiting and nausea, it is also available in the form of a suppository.
How it Works
According to the National Institutes of Health (NIH), dimenhydrinate consists of a combination of diphenhydramine and 8-chlorotheophylline that help correct problems related to balance that can cause nausea. Diphenhydramine is an antihistamine typically found in allergy preparations and over-the-counter sleep aids that produces a calming effect on the muscarinic acetylcholine receptors located in the plasma membrane of neurons. 8-chlorotheophylline is derived from theophylline, which is similar to caffeine in its stimulating effect on the central nervous system and helps offset the effects of drowsiness caused by diphenhydramine.
A 1993 study by the Departments of Psychology and Medicine at Penn State University found that dimenhydrinate has the ability to help suppress gastric tachyarrhythmia caused by visual stimuli, which can cause nausea and vomiting. The researchers concluded that "dimenhydrinate is effective in reducing the symptoms of vection-induced motion sickness, and that the mechanism of this effect involves inhibition of a specific peripheral response, such as gastric tachyarrhythmia, in response to the conflicting visual-vestibular inputs produced by a rotating optokinetic drum." A follow-up study two years later by the same researchers further concluded that "dimenhydrinate reduced motion sickness symptoms at least in part by depressing central nervous system activity and possibly by suppressing abnormal gastric myoelectric activity."
The NIH indicates a number of precautions before using dimenhydrinate. NIH recommends speaking to a doctor if taking other prescription of over-the-counter medications before using dimenhydrinate, and also recommends doing the same if there is a history of any of the following conditions: asthma, enlarged prostate, phenylketonuria, if currently pregnant or breastfeeding, or if about to have surgery. NIH also recommends avoiding the operation of motor vehicles and alcoholic beverages after taking dimenhydrinate.
The NIH reports that dimenhydrinate may cause the following side effects: dizziness, fainting, coordination problems, dry mouth, headache, hyperactivity, blurred vision, ringing in the ears, nausea, and rapid or irregular heartbeat.
The NIH also indicates that overdose is a possibility of dimenhydrinate, and that signs of overdose may include: flushed face, enlarged pupils, seizures, confusion, unresponsiveness, hallucinations, hyperactivity, drowsiness, and difficulty speaking. If overdose is suspected, NIH recommends calling a local poison control center immediately.