Dimenhydrinate is anover-the-counter (OTC) first-generationantihistamine indicated for the prevention and relief of nausea and vomiting from a number of causes, including motion-sickness and post-operative nausea.[2]
Common side effects of dimenhydrinate may includedrowsiness,dry mouth, nose, or throat,constipation, andblurred vision. Some individuals, particularly children, may experience feelings ofrestlessness or excitement. In certain cases, more severe symptoms may arise, such asdelirium, weakness, and a tendency to be easilystartled.Hallucinations,psychosis, and an unusual sensitivity to sudden sounds have also been reported.[5][6][7] Continuous and/or cumulative use ofanticholinergic medications, including first-generation antihistamines, is associated with higher risk of cognitive decline and dementia in older people. However, in younger people this is not relevant.[8][9]
Diphenhydramine is the primary constituent of dimenhydrinate and dictates the primary effect. The main differences relative to pure diphenhydramine are a lowerpotency due to being combined with 8-chlorotheophylline (by weight, dimenhydrinate is between 53% and 55.5% diphenhydramine)[10] and the fact that the stimulant properties of 8-chlorotheophylline help reduce the side effect of drowsiness brought on by diphenhydramine. Diphenhydramine is itself anH1 receptorantagonist that demonstratesanticholinergic activity.[11]
The diphenhydramine component requires about 2hours to reach peak concentration after either oral or sublingual administration of dimenhydrinate, and has a half-life of5 – 6hours in healthy adults.[1]
Dimenhydrinate is recreationally used as adeliriant.[12][13][14] Slang terms for Dramamine used this way include "drama", "dime", "dime tabs", "D-Q", "substance D", "d-house", and "drams".[15] Abusing Dramamine is sometimes referred to as Dramatizing or "going a dime a dozen", a reference to the number of Dramamine tablets generally necessary for a recreational dose.[16]
Dimenhydrinate (originally known as Compound 1694) was being tested as a potential treatment forhay fever andhives atJohns Hopkins Hospital in 1947 by allergists Dr. Leslie Gay and Dr. Paul Carliner. Among those who received the drug was a pregnant woman who had suffered from motion sickness her entire life. She remained symptom-free if she took dimenhydrinate a few minutes before boarding a trolley, whereas the placebo was ineffective. To confirm these findings, the following year, G.D. Searle & Co. conducted a trial in which dimenhydrinate or placebo was given to U.S. troops crossing the Atlantic during "a rough passage" in a converted freight ship, theGeneral Ballou, for ten days as a rescue therapy forsea sickness. The findings were positive, as were the findings of a second trial of mostly women on the ship's return voyage. Gay and Carliner announced their discovery at a meeting of the Johns Hopkins Medical Society on February 14, 1949, as well as in theBulletin of The Johns Hopkins Hospital. TheNew York Times, theBaltimore Sun, and other national newspapers covered the discovery, and Dramamine was made available in drugstores later that year.[3][4][19]
^abScavone JM, Luna BG, Harmatz JS, von Moltke L, Greenblatt DJ (April 1990). "Diphenhydramine kinetics following intravenous, oral, and sublingual dimenhydrinate administration".Biopharmaceutics & Drug Disposition.11 (3):185–189.doi:10.1002/bdd.2510110302.PMID2328304.
^Fabiano N, Dholakia S, Walker LA, Smith AL (March 2024). "Chronic high-dose dimenhydrinate use contributing to early multifactorial cognitive impairment".BMJ Case Reports.17 (3) e258493.doi:10.1136/bcr-2023-258493.PMC 10921430.PMID38453220.
^Canadian Agency for Drugs and Technologies in Health (2015). "Abuse and Misuse Potential of Dimenhydrinate: A Review of the Clinical Evidence [Internet]".CADTH Rapid Response Reports.PMID26985532.
^Scharman EJ, Erdman AR, Wax PM, Chyka PA, Caravati EM, Nelson LS, et al. (19 January 2006). "Diphenhydramine and dimenhydrinate poisoning: an evidence-based consensus guideline for out-of-hospital management".Clinical Toxicology.44 (3):205–223.doi:10.1080/15563650600585920.PMID16749537.S2CID702353.
N
Y (what is this?) (verify)
Media related toDimenhydrinate at Wikimedia Commons