Gamma hydroxybutyrate toxicity: Difference between revisions
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*usually young white male from nightclub | *usually young white male from nightclub | ||
*can have | *can have nausea and vomiting, resp deprsn, bradycardia, seizure | ||
*get euphoria s hang over | *get euphoria s hang over | ||
*can also get ataxia, nystagmus, somnolence and aggression | *can also get ataxia, nystagmus, somnolence and aggression | ||
Revision as of 05:25, 14 July 2016
Background
- Abbreviation: GHB
- Frequently referred to as the "date rape drug"
- Central nervous system depressant
- GABA-B agonist (as opposed to GABA-A agonists - alcohol, benzodiazepines, etc)
- Abused for:
- Body building or sleep enhancement
- euphoric, sexual, stimulant, and relaxant effects
- Surreptitious drugging to facilitate sexual assault
- Also used therapeutically in the treatment of narcolepsy[1]
Pharmacokinetics
- Effects start in 15-20 minutes, peak in 30-60 minutes,
- Lipid soluble, readily crosses the blood brain barrier
- Elimination is dose-dependent; half-life of 20-50 minutes
- The duration of GHB's clinical effects depends upon the dose, and ranges from 2.5-4 hours
Pharmacology
- Is a metabolite and precursor of GABA
- Interacts with GHB-specific receptors and also acts as a direct agonist of GABA-B receptors
- Affects multiple neurotransmitter systems, including those of opioids, dopamine, serotonin, glutamate, and acetylcholine
- Gamma butyrolactone (GBL) and 1,4 butanediol (BD) are GHB analogs that are rapidly metabolized to GHB after ingestion, with the same toxic and recreational effects
Clinical Features
- cns and resp depression
- also cardioa and gi symptoms
- many times have cointoxicants
- usually young white male from nightclub
- can have nausea and vomiting, resp deprsn, bradycardia, seizure
- get euphoria s hang over
- can also get ataxia, nystagmus, somnolence and aggression
- resp/ cns deprrsion resolves abruptly
- resp depression worse with other cns depressants-alcohol
- periods of apnea and hyperventilation-is periodic breathing
- decreases resp rate but tidal vol increases so minute vol stable
- can also have seizure but eeg shows no epileptiform changes
- bradycardia, hypotension*ekg change occasionally but rare
- also get vomitting, hypothermia
Clinical Course
- recover 2-6 hrs
- may be extubated and sent home
- if longer than 6hr, look for other cause
- can have cross tolerance with other drugs-alcohol and others that effect liver p450 cytochome oxidase system
Differential Diagnosis
Sedative/hypnotic toxicity
- Absinthe
- Barbiturates
- Benzodiazepines
- Chloral hydrate
- Gamma hydroxybutyrate (GHB)
- Baclofen toxicity
- Opioids
- Toxic alcohols
- Xylazine toxicity
Drugs of abuse
- 25C-NBOMe
- Alcohol
- Amphetamines
- Bath salts
- Cocaine
- Ecstasy
- Gamma hydroxybutyrate (GHB)
- Heroin
- Inhalant abuse
- Hydrocarbon toxicity
- Difluoroethane (electronics duster)
- Marijuana
- Kratom
- Phencyclidine (PCP)
- Psilocybin ("magic mushrooms")
- Synthetic cannabinoids
- Chloral hydrate
- Body packing
Diagnosis
- Not detectable on routine toxicology screens
Management
- supportive
- look for coingestants and occult trauma
- charcoal not helpful since rapidly absorbed and since can vomit and aspirate
- protein bound so can use dialysis*but so short course usually do not need.
Antidotes
- flumazenil/ narcan helps in animals but not in humans
- physostigmine may reverse coma but if have coingestant is dangerous-may lower seizure threshold
Disposition
See Also
References
- ↑ Mamelak M, Scharf MB, Woods M. Treatment of narcolepsy with gamma-hydroxybutyrate. A review of clinical and sleep laboratory findings. Sleep. 1986;9(1 Pt 2):285-289. doi:10.1093/sleep/9.1.285