dimenhydrinate

Action and Spectrum

Actions and Spectrum:

The actions and spectrum of dimenhydrinate can be broken down into the following categories:

Antiemetic: dimenhydrinate is an effective antiemetic, meaning it helps to prevent or reduce nausea and vomiting. This is particularly useful for preventing and treating motion sickness.

Antihistamine: As an antihistamine, dimenhydrinate blocks the action of histamine, which can cause symptoms such as itching, sneezing, runny nose, and watery eyes.

Sedative: dimenhydrinate can have a sedative effect, which can help to reduce feelings of anxiety and promote relaxation.

Anticholinergic: dimenhydrinate has anticholinergic properties, which means it can help to reduce muscle spasms and control involuntary muscle contractions.

Antivertigo: dimenhydrinate can also help to reduce symptoms of vertigo, such as dizziness and spinning sensations.

Overall, the actions and spectrum of dimenhydrinate make it a useful medication for preventing and treating a range of symptoms related to motion sickness, vertigo, and nausea.

Drug Interaction

Adverse Reaction

Frequency Not Defined 

CNS depression

Dizziness

Drowsiness

Lassitude

Muscular weakness

Paradoxical CNS stimulation

Disturbed coordination

Restlessness

Anorexia

Epigastric distress

Nausea

Diarrhea

Vomiting

Black Box Warning

Black Box Warning

dimenhydrinate, a medication used to prevent and treat nausea, vomiting, and dizziness, carries a black box warning due to the risk of adverse effects on the central nervous system.

Contraindication / Caution

Contraindication/Caution:

dimenhydrinate is contraindicated in individuals with a known hypersensitivity to the medication or its ingredients. It should also be used with caution in individuals with cardiovascular or respiratory disorders, as well as in those with a history of glaucoma or urinary retention.

The use of dimenhydrinate should be avoided in individuals who are taking other medications that may cause drowsiness, such as sedatives, hypnotics, or opioid analgesics. Additionally, individuals who are pregnant or breastfeeding should consult with a healthcare provider before taking dimenhydrinate.

Pregnancy / Lactation

Pregnancy warnings:   

US FDA pregnancy category: B

Lactation:  

Excreted into human milk is known

Pregnancy Categories:        

Category A: Studies that were well-controlled and met expectations revealed no risk to the fetus in either the first or second trimester.

Category B: There were lack of studies on pregnant women and no evidence of risk to the foetus in animal experiments.

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.

Category D: adequate data available with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.

Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.

Category N: There is no data available for the drug under this category

Pharmacology

Pharmacology: 

dimenhydrinate, also known as Dramamine, is a medication that belongs to a class of drugs called antihistamines. It is commonly used to treat symptoms of motion sickness such as nausea, vomiting, and dizziness.

Pharmacodynamics: 

The active ingredient in dimenhydrinate is diphenhydramine, which blocks the action of a neurotransmitter called histamine. Histamine is released in the body in response to certain stimuli, such as motion, and can cause symptoms such as nausea and vomiting. By blocking the action of histamine, dimenhydrinate is able to reduce these symptoms.

Pharmacokinetics:  

Absorption 

dimenhydrinate is rapidly absorbed after oral administration and reaches peak plasma concentrations within 1-2 hours.

Distribution 

It is highly protein-bound and distributes throughout the body, including the brain and central nervous system.

Metabolism 

dimenhydrinate is metabolized in the liver by the enzyme CYP3A4, resulting in the formation of several active and inactive metabolites.

Elimination and Excretion 

dimenhydrinate and its metabolites are primarily excreted in the urine. The half-life of dimenhydrinate is approximately 4-6 hours.

Adminstartion

Administration: 

dimenhydrinate is typically administered orally in tablet or capsule form. The dosage and frequency of administration will depend on the specific condition being treated and the individual’s response to the medication.

Common dosages for motion sickness:

• Adults: 50-100 mg every 4-6 hours as needed
• Children (6-12 years): 25-50 mg every 4-6 hours as needed

Common dosages for vertigo:

• Adults: 50-100 mg every 4-6 hours as needed

It is important to follow the dosage instructions provided by a healthcare provider and to not exceed the recommended dosage. dimenhydrinate can cause drowsiness and should not be taken with alcohol or other sedating medications. It should also not be taken by individuals with certain medical conditions such as glaucoma, prostate problems, or high blood pressure.

Patient Information Leaflet

Patient information leaflet

Generic Name: dimenhydrinate

Why do we use dimenhydrinate?

dimenhydrinate is a medication that is primarily used to treat and prevent symptoms of motion sickness, such as nausea, vomiting, and dizziness. It works by blocking the action of histamine, a chemical in the body that causes these symptoms, and by stimulating the vestibular system, which helps to reduce dizziness.

dimenhydrinate is also used to treat vertigo, which is a type of dizziness caused by inner ear problems. It helps to reduce the symptoms of vertigo, such as a spinning sensation, unsteadiness, and loss of balance.