Lorazepam, sold under the brand name Ativan among others, is a benzodiazepine medication. It is used to treat anxiety (including anxiety disorders), insomnia, severe agitation, active seizures including status epilepticus, alcohol withdrawal, and chemotherapy-induced nausea and vomiting. It is also used during surgery to interfere with memory formation, to sedate those who are being mechanically ventilated, and, along with other treatments, for acute coronary syndrome due to cocaine use.[20][21] It can be given orally (by mouth), transdermally (on the skin via a topical gel or patch), intravenously (injection into a vein), or intramuscularly (injection into a muscle).[20] When given by injection, onset of effects is between one and thirty minutes and effects last for up to a day.[20]
Common side effects include weakness, sleepiness, dizziness, decreased alertness, decreased memory formation, low blood pressure, and a decreased effort to breathe.[20] When given intravenously, the person is typically closely monitored.[20] Among those who are depressed, there may be an increased risk of suicide.[20][22] With long-term use, tolerance may develop, with larger doses required for the same effect.[20] Physical dependence and psychological dependence may also occur.[20] If stopped suddenly after long-term use, benzodiazepine withdrawal syndrome may occur.[20]
Lorazepam was initially patented in 1963 and went on sale in the United States in 1977.[26][27] It is on the World Health Organization's List of Essential Medicines.[28] It is available as a generic medication.[20] In 2023, it was the 100th most commonly prescribed medication in the United States, with more than 6million prescriptions.[29][30]
Medical uses
Anxiety
Lorazepam is used in the short-term management of severe anxiety. In the US, the Food and Drug Administration (FDA) advises against use of benzodiazepines such as lorazepam for longer than four weeks.[25][31] It is fast-acting, and useful in treating fast-onset anxiety and panic attacks.[32]
Lorazepam can effectively reduce agitation and induce sleep, and the duration of effects from a single dose makes it an appropriate choice for the short-term treatment of insomnia, especially in the presence of severe anxiety or night terrors. It has a fairly short duration of action.[33]
Withdrawal symptoms, including
Adverse effects
Many beneficial effects of lorazepam (e.g., sedative, muscle relaxant, anti-anxiety, and amnesic effects) may become adverse effects when unwanted.[43] Adverse effects can include sedation and low blood pressure; the effects of lorazepam are increased in combination with other CNS depressants.[35][50] Other adverse effects include confusion, ataxia, inhibiting the formation of new memories, pupil constriction, and hangover effects. With long-term benzodiazepine use, it is unclear whether cognitive impairments fully return to normal after stopping lorazepam use; cognitive deficits persist for at least six months after withdrawal, but longer than six months may be required for recovery of cognitive function. Lorazepam appears to have more profound adverse effects on memory than other benzodiazepines; it impairs both explicit and implicit memory.[63][64]
Pharmacology
Lorazepam has anxiolytic, sedative, hypnotic, amnesic, anticonvulsant, and muscle relaxant properties.[96] It is a high-potency and an benzodiazepine, and its uniqueness,[97][98] advantages, and disadvantages are largely explained by its pharmacokinetic properties (poor water and lipid solubility, high protein binding and anoxidative metabolism to a pharmacologically inactive glucuronide form) and by its high relative potency (lorazepam 1 mg is equal in effect to diazepam 10 mg).[99][100] The biological half-life of lorazepam is 10–20 hours.[101]
History
Historically, lorazepam is one of the "classical" benzodiazepines. Others include diazepam, clonazepam, oxazepam, nitrazepam, flurazepam, bromazepam, and clorazepate.[115] Lorazepam was introduced by Wyeth Pharmaceuticals in 1977 under the brand names Ativan and Temesta.[116] The drug was developed by D.J. Richards, president of research. Wyeth's original patent on lorazepam is expired in the United States.
Society and culture
Recreational use
Lorazepam is also used for other purposes, such as recreational drug use, wherein it is taken to achieve a high, or when the medication is continued long-term against medical advice.[117]
A 2006 large-scale, nationwide, US government study of pharmaceutical-related emergency department visits by SAMHSA found sedative-hypnotics are the pharmaceuticals most frequently used outside of their prescribed medical purpose in the United States, with 35% of drug-related emergency department visits involving sedative-hypnotics. In this category, benzodiazepines are most commonly used. Males and females use benzodiazepines for nonmedical purposes equally. Of drugs used in attempted suicide, benzodiazepines are the most commonly used pharmaceutical drugs, with 25% of attempted suicides involving them and lorazepam specifically being used in 3.6% of attempts. Lorazepam was the third-most-common benzodiazepine used outside of prescription in these ER visit statistics.[118]
Legal status
External links
- Lorazepam data sheet IPCS INCHEM
- Lorazepam Online Online
References
- Lorazepam The Drug Gene Interaction Database, retrieved 18 May 2016^
- Pharmacology for the Primary Care Provider Mosby, 2013, retrieved 13 July 2020^
- Clinical Addiction Psychiatry Cambridge University Press, 2010^