Diclazepam (also known as chlorodiazepam, 2′-chloro-diazepam, Ro5-3448) belongs to benzodiazepine class of drugs and is an analogue of diazepam. It was first synthesised in the 1960s at the pharmaceutical firm Hoffman-La-Roche by the chemist Leo Stembach. It is noted for having effects comparable to diazepam in that it is an anxiolytic, hypnotic, amnestic, depressant, sedative and anticonvulsant. In animal studies it has ten times the potency of diazepam.
Diclazepam has the formal and systematic name 7-chloro-5-(2-chlorophenyl)-1-methyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one. It has a relative molar mass of 319.185 grams and empirical formula C16H12Cl2N2O. Diclazepam is metabolised at the liver. It has a biological half life of 43 hours and is excreted at the kidneys. Common routes of administration are oral and sublingual. It is not currently being marketed as a medicine in humans.
Diclazepam, like other benzodiazepines, exerts its effect by binding to an allosteric site at GABAa. It increases the total chloride ion conduction across the neuronal membrane whilst GABA is bound to the GABAa receptor. Thus diclazepam acts to increase the effect of GABA which is the chief inhibitory neuron in the mammalian CNS. Increasing the efficiency of GABA produces the variety of depressant effects such as sedation and reduction of anxiety.
Diclazepam is not for human or animal consumption.
Subjective online reports mention a variety of effects produced by diclazepam.
It is reported as being extremely sedating and produces an overwhelming feeling of lethargy. Diclazepam is also reported as producing the following physical effects – respiratory depression, muscle relaxation, dizziness and loss of control of body movement.
Cognitive effects of diclazepam are reported as increasing in intensity proportional to increase in dosage. Users have described loss of inhibition and intense sedation. Along with this diclazepam is said to suppress anxiety and dull emotions, slow or impair thinking and produce states of amnesia. Users are often unaware of the extent of their intoxication and may be under the illusion that they are more sober than in reality. Furthermore it is associated with a compulsion to re-dose.
Sudden discontinuation of it after sustained usage is likely to produce benzodiazepine discontinuation syndrome which can be life threatening. It is recommended for use in the short term and discontinuation must be accompanied by a general tapering off of the dose.
it is both physically and psychologically addictive. Additionally tolerance will build within a few days of continual use. Tolerance is reported as returning to baseline levels within one to two weeks after cessation. Tolerance may persist after cessation for longer periods of time in long term users.
it has a low potential for toxicity when taken alone. However it can be lethal when used in combination with other drugs.
Combination with depressants such as alcohol, GBH/GBL, opioids or barbiturates can result in fatal respiratory depression. Combination with dissociative substances such as ketamine increases the risk of vomiting during periods of unconsciousness. Combination with stimulants such as cathinones, cocaine, MDMA or amphetamines may also be toxic. Stimulants counteract the sedative effect of hypnotics like diclazepam encouraging use of higher doses. When the stimulant wears off the sedative effect of the hypnotic can be too great resulting in death.