Baclofen toxicity

Baclofen toxicity
Other names: Baclofen poisoning, baclofen overdose
Russian baclofen 25 mg tablets with the warning "this drug may cause psychomotor retardation"
Specialty	Toxicology
Symptoms	Confusion, slow heart rate, low blood pressure, increased saliva[1]
Complications	Coma, seizures[1]
Usual onset	Within 2 to 4 hrs[2]
Causes	>200 mg in and adult[2]
Risk factors	poor kidney function[1]
Differential diagnosis	Sepsis, intracranial bleed, low blood sugar, low thyroid, opioid overdose, adrenal crisis, brain death[1][3]
Treatment	Supportive care (intubation), activated charcoal[1][2]
Prognosis	Often resolves over 1 to 2 days[3]
Frequency	~5,000 reported cases (USA, 2020)[3]

Baclofen toxicity, also known as baclofen poisoning, is a life threatening condition due to excessive baclofen.^[3] Symptoms often include slow heart rate, low blood pressure, increased saliva, low body temperature, and confusion.^[1] Though the heart rate may be fast and the blood pressure high.^[2] Other complications may include coma or seizures.^[1]

In adults a dose of more then 200 mg generally results in problems within 2 hours.^[2] This can occur by mouth or via an intrathecal pump.^[3] Risk factors include poor kidney function, particularly a GFR less than 30 ml/min.^[1] If a person has no symptom more than four hours after exposure toxicity is unlikely to occur.^[2] Blood levels for baclofen are generally not availiable.^[3]

Management involves supportive care such as intubation.^[1] After intubation activated charcoal may be used.^[2] Dialysis may be recommended in those with kidney problems.^[1] Seizures are treated with benzodiazepines while low blood pressure may be managed with intravenous fluids and norepinephrine.^[2] Symptoms often resolves over 1 to 2 days.^[3] Following recovery baclofen generally requires restarting or withdrawal may occur.^[2]

In 2020 nearly five thousand overdoses were documented by the America's Poison Centers with four deaths.^[3] About 20% receiving the medication via a pump develop problems at some point.^[3] In those who overdose intentionally, the typical age is around 35 and slightly over half are women.^[3]

References