Talk:Doxylamine
Doxylamine is a first generation antihistamine affecting histamine at H1 receptors. In addition, it has powerful anticholinergic effects.
Medical Uses
Doxylamine is used with pyridoxine to prevent morning sickness. It's also used as a sleep aid useful for alleviating short-term insomnia, and is a useful anti-tussive agent.
Metabolites
The primary metabolites of doxylamine are-
- N-desmethyldoxylamine
- N,N-didesmethyldoxylamine
- doxylamine N-oxide
Side Effects
- Ataxia
- Dry mouth
- Urinary Retention
- Short-term Memory Failure
- Inability to Concentrate
- Hallucinations
Toxicity
Doxylamine succinate is generally safe for administration to healthy adults. The median lethal dose (LD50) is estimated to be 50–500 mg/kg in humans. Symptoms of overdose may include dry mouth, dilated pupils, insomnia, night terrors, euphoria, hallucinations, seizures, rhabdomyolysis, and death. Fatalities have been reported from doxylamine overdose. These have been characterized by coma, tonic-clonic (or grand mal) seizures and cardiorespiratory arrest. Children appear to be at a high risk for cardiorespiratory arrest. A toxic dose for children of more than 1.8 mg/kg has been reported. A 3-year old child died 18 hours after ingesting 1,000 mg doxylamine succinate. Rarely, an overdose results in rhabdomyolysis and acute renal failure.
Studies of doxylamine's carcinogenicity in mice and rats have produced positive results for both liver and thyroid cancer, especially in the mouse. The carcinogenicity of the drug in humans is not well studied, and the IARC lists the drug as "not classifiable as to its carcinogenicity to humans".
References
https://www.ncbi.nlm.nih.gov/pubmed/1975634
https://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@term+@DOCNO+5184