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Temazepam (marketed under brand names Restoril®, Normison®, Tenox® and Temaze®) is a powerful hypnotic drug, which is a benzodiazepine derivative. It possesses powerful anxiolytic, anticonvulsant, amnestic, sedative and skeletal muscle relaxant properties. History Until recently temazepam was produced as a gel-filled capsule intended to be taken orally. However, it gained a certain notoriety in the United Kingdom, and especially Scotland, when it was discovered that if the capsules were melted and injected the effects were more potent and similar to alcohol. However, the liquid has a tendency to congeal in arteries and cause thrombosis and gangrene, in some cases requiring amputation. Pharmacology The pharmacological action of temazepam is thought to be the result of its facilitating the action of gamma aminobutyric acid, an inhibitor neurotransmitter. Temazepam is an active benzodiazepine with powerful hypnotic properties and is the most sedating of all benzodiazepines. In sleep laboratory studies, temazepam dramatically decreased the number of nightly awakenings. Rebound insomnia was not observed after withdrawal of the drug. Temazepam decreased stage 3, and combined stage 3 and 4 sleep, accompanied by a compensatory increase in stage 2 sleep, but did not alter REM sleep. Orally administered temazepam is well absorbed in humans. Temazepam has a half-life of about 8 to 10 hours in plasma (with considerable inter-individual variability). On multiple dosing, steady state is reached usually within 3 to 5 days with excretion of the drug mainly in the urine in the form of the inactive O-conjugate metabolite. Indications Temazepam is commonly prescribed for insomnia and other serious sleep disorders. Temazepam is considered to be one of the most addictive of the benzodiazepines and thus not suited for long-term treatment. Street terms include "rugby balls", "terms", "jellies", "mazzies", "beans" and "eggs". Military Use The United States Air Force uses temazepam under trade name Restoril as "no-go pills" to help pilots sleep after a mission (Cf. "go-pills"; dextroamphetamine, or recently modafinil, used as a stimulant for pilots). Another drug used for the same purpose is zolpidem. Dosage Temazepam is available in 7.5mg, 15mg, 22.5mg and 30mg capsules. It is available as 10 and 20mg tablets in the UK and Finland, but also in at least some countries in the rest of Europe. In Australia it is only available in 10mg tablets. 20mg tablets and Temazepam in capsule or gelcap form is no longer available in this country. When used for treatment of insomnia, the usual dose is 7.5mg to 15mg taken at bedtime but can be used at doses up to 60mg. Usual UK doses (from BNF) are 10-20mg at bedtime, max 30-40mg in exceptional circumstances. Side effects Common side effects include: Rare side effects include: Before taking temazepam, one should ensure that at least 8 hours are available to dedicate to sleep. Failing to do so can increase the side effects of the drug. Long-term use of temazepam can result in psychological and physical dependence and the appearance of withdrawal symptoms when the drug is discontinued. Temazepam impairs cognitive and psychomotor functions, affecting reaction time and driving skill. The use of this drug in combination with alcohol potentiates these side effects, and can lead to toxicity and death. Interactions See Diazepam#Interactions. Contraindications Use of temazepam should be avoided, when possible, in individuals with the following conditions: Special caution needed Patients at a high risk for abuse and dependence Temazepam can lead to physiological tolerance, and psychological and/or physical dependence. At a particularly high risk for temazepam misuse, abuse, and dependence are: Patients from the aforementioned groups should be monitored very closely during therapy for signs of abuse and development of dependence. Discontinue therapy if any of these signs are noted. Long-term therapy in these patients is not recommended. Overdose Manifestations of acute overdosage of temazepam can be expected to reflect the increasing CNS effects of the drug and include: Temazepam overdose is considered a serious medical emergency and generally requires the immediate attention of medical personnel. The antidote for an overdose of temazepam (or any other benzodiazepine) is flumazenil (Anexate®). If the patient is conscious, vomiting should be induced mechanically or with emetics (e.g., syrup of ipecac 20 to 30 mL). Gastric lavage should be employed as soon as possible, utilizing concurrently a cuffed endotracheal tube if the patient is unconscious, in order to prevent aspiration and pulmonary complications. Maintenance of adequate pulmonary ventilation is essential and fluids should be administered IV to encourage diuresis. The use of pressor agents IV, may be necessary to combat hypotension but only if considered essential. The value of dialysis in emergency therapy for benzodiazepine overdosage has not been determined. If excitation occurs, barbiturates should not be used. It should be borne in mind that multiple agents may have been ingested. The oral LD50 of temazepam was 1963 mg/kg in mice, 1833 mg/kg in rats, and >2400 mg/kg in rabbits. Legal Status Temazepam is a Class C drug in the United Kingdom and possession is illegal without a prescription. Additionally, all manufacturers in the UK have replaced the gel-capsules with solid tablets. In the US, temazepam is a Schedule IV drug and is only available by prescription. Certain states require specially coded prescriptions for this medication. Internationally, temazepam is a Schedule IV drug under the Convention on Psychotropic Substances*. In Canada Temazepam can be issued as a standard prescription by any family doctor who sees a need for it. In Australia Temazepam is Schedule 4 requiring a doctors prescription no repeats are allowed. All Schedule 4 drugs can only be obtained from a pharmacy in the same state or territory in which the prescription was issued. Trivia The recreational effects of the drug were documented in the Black Grape album, It's Great When You're Straight... Yeah. The track 'Tramazi Parti' contains the lyric: I got my boots on the back of my head / It's full of jellies in the good old bed / And no one knows what no one said. Although there is no medical research confirming this behaviour, it is not inconsistent with the known side effects of the drug. | |||||||
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