Lorazepam is a benzodiazepine drug used for various conditions. Being a benzodiazepine, it has various functions such as being an anxiolytic, sedative or hypnotic, amnesic, antiemetic, anticonvulsant and muscle relaxant. Lorazepam is available under the brand names of Temesta and Ativan. Lorazepam has a very high potential for addiction because of its short-acting effects. It also has the potential for tolerance and drug withdrawal, which tend to be life-threatening. Lorazepam exerts its effects by binding on the GABA receptors located in the Central Nervous System (CNS).
Lorazepam Overdose Amount
An overdose amount of lorazepam in adults is more than 8 mg a day. Others may begin to develop significant effects in as little as 4 mg in a day. For pediatric clients, more than 2 mg of lorazepam in a day may already cause lorazepam overdose.
Symptoms of Lorazepam Overdose
The effects of lorazepam overdose are due to the excessive action of the GABA in the CNS. Because of this, there is excessive inhibition of the CNS process leading to the following symptoms:
1. Mental confusion
Since GABA is an inhibitory neurotransmitter, too much level of lorazepam leads to severe inhibition of CNS functions that may lead to metal confusion.
2. Paradoxical reactions
Lorazepam overdose may also lad to paradoxical reactions, specifically seizures. Lorazepam is an anticonvulsant, but may result in paradoxical seizures in cases of lorazepam overdose.
The speech center in the frontal lobe may also be affected leading to difficulty forming and initiating speech.
4. Drowsiness and hypnosis
The decreased nerve impulse transmission in the brain also leads to altered level of consciousness. Too much hypnotic effect may lead to prolonged hypnosis.
The cerebellar function may also be impaired in lorazepam overdose leading to ataxia or unstable gait.
Decreased brain activity also slows down the nerve impulses to the motor cortex leading to decreased muscle strength and tone.
Apparently, GABA receptors are also present in the smooth muscles in the cardiovascular system. This may lead to excessive dilation of the blood vessels causing hypotension.
8. Cardiovascular depression
The myocardial contractility may also be affected. Hypotension and cardiac problems may result in cardiac depression that may potentially lead to cardiovascular collapse.
9. Respiratory depression
Respiratory depression is a potentially life-threatening effect of lorazepam overdose. The respiratory center in the brain is commonly affected leading to decreased depth and rate of breathing that may eventually lead to apnea or absence of respiration.
Severe inhibition of the central nervous system in lorazepam overdose may result in irreversible coma.
Causes of Lorazepam Overdose
Lorazepam overdose is usually caused by accidental or intentional ingestion of large doses of lorazepam. Because of its amnesic and hypnotic effect, lorazepam is also used for criminal purposes in large doses leading tolorazepam overdose among victims.
Diagnosis of Lorazepam Overdose
The normal blood level of lorazepam is 10 to 300 ug/L. Lorazepam overdose may reach up to 300 to 1000 ug/L in the blood.
Treatment of Lorazepam Overdose
Treatment of lorazepam overdose may involve the following:
1. Induction of vomiting
Vomiting is usually induced in alert patients in order to remove the excessive drug levels in the stomach.
2. Gastric lavage with activated charcoal
Gastric lavage is done to wash the stomach. Activated charcoal is also given to allow the carbon to absorb the toxin and prevent intestinal absorption of the drug.
3. Administration of antidote
Flumazenil is the antidote for benzodiazepine overdose. It competes at the GABA receptors in order to prevent binding of the benzodiazepine in the receptor sites, thereby reversing the symptoms.
Other managements of lorazepam overdose are supportive such as respiratory and cardiovascular support. In order to prevent other drug overdose like folic acid overdose, it is important to adhere with the prescription of the physician and never increase the dosage on your own.