Camazepam, like others benzodiazepines, produce a variety of therapeutic and adverse effects by binding to the benzodiazepine receptor site on the GABAA receptor and modulating the function of the GABA receptor, the most prolific inhibitory receptor within the brain. The GABA chemical and receptor system mediates inhibitory or calming effects of camazepam on the nervous system.
Compared to other benzodiazepines, it has reduced side effects such as impaired cognition, reaction times and coordination,[5][6][7][8][9] which makes it best suited as an anxiolytic because of these reduced sides effects.
Animal studies have shown camazepam and its active metabolites possess anticonvulsant properties.[10]
Unlike other benzodiazepines it does not disrupt normal sleep patterns.[11] Camazepam has been shown in animal experiments to have a very low affinity for benzodiazepine receptors compared to other benzodiazepines.[12] Compared to temazepam, camazepam has shown roughly equal anxiolytic properties, and less anticonvulsant, sedative, and motor-impairing properties.
Pharmacokinetics
Following oral administration, camazepam is almost completely absorbed into the bloodstream, with 90 percent bioavailability achieved in humans.[13]
In the human camazepam is metabolised into the active metabolitetemazepam.[14] Studies in dogs have shown that the half-life of the terminal elimination phase ranged from 6.4 to 10.5 h.[15]
Medical uses
Camazepam is indicated for the short-term treatment of insomnia and anxiety.[16] As with other benzodiazepines, its use should be reserved for patients in which the sleep disorder is severe, disabling, or causes marked distress.[17]
Adverse effects
With higher doses, such as 40 mg of camazepam, impairments similar to those caused by other benzodiazepines manifest as disrupted sleep patterns and impaired cognitive performance.[18]Skin disorders have been reported with use of camazepam however.[19] One study has shown that camazepam may increase attention.[20]
Research has demonstrated that Camazepam exhibits competitive binding to benzodiazepine receptors within the brain, albeit with a relatively modest affinity in animal models. This interaction with benzodiazepine receptors, facilitated by both Camazepam and its active metabolites, is accountable for the medication's anticonvulsant properties.[1]
Contraindications
Use of camazepam is contraindicated in subjects with known hypersensitivity to drug or allergy to other drugs in the benzodiazepine class or any excipients contained in the pharmaceutical form. Use of camazepam should be avoided or carefully monitored by medical professionals in individuals with the following conditions: myasthenia gravis, severe liver deficiencies (e.g., cirrhosis), severe sleep apnea, pre-existing respiratory depression or cronic pulmonary insufficiency.[21]
^DE 2142181, "1,4 Benzodiazepine derivatives and process for their production", issued 23 December 1976, assigned to Siphar S A , Lugano (Schweiz).
^Tammaro A, Picceo MT, Gemmellaro P, Bonaccorso O (1977). "Camazepam versus placebo. A double-blind clinical study on geriatric patients suffering from psychic complaints. Short Communication". Arzneimittel-Forschung. 27 (11): 2177–2178. PMID23793.
^Lu XL, Yang SK (April 1994). "Enantiomer resolution of camazepam and its derivatives and enantioselective metabolism of camazepam by human liver microsomes". Journal of Chromatography A. 666 (1–2): 249–257. doi:10.1016/0021-9673(94)80387-0. PMID7911374.
^De Sarro G, Chimirri A, Zappala M, Guisti P, Lipartiti M, De Sarro A (October 1996). "Azirino[1,2-d][1,4]benzodiazepine derivatives and related 1,4-benzodiazepines as anticonvulsant agents in DBA/2 mice". General Pharmacology. 27 (7): 1155–1162. doi:10.1016/S0306-3623(96)00049-3. PMID8981061.
^De Sarro G, Gitto R, Rizzo M, Zappia M, De Sarro A (September 1996). "1,4-Benzodiazepine derivatives as anticonvulsant agents in DBA/2 mice". General Pharmacology. 27 (6): 935–941. doi:10.1016/0306-3623(95)02147-7. PMID8909973.
^De Sarro G, Chimirri A, McKernan R, Quirk K, Giusti P, De Sarro A (September 1997). "Anticonvulsant activity of azirino[1,2-d][1,4]benzodiazepines and related 1,4-benzodiazepines in mice". Pharmacology, Biochemistry, and Behavior. 58 (1): 281–289. doi:10.1016/S0091-3057(96)00565-5. PMID9264104. S2CID24492818.
^Guthy H (August 1975). "[The medicinal treatment of anxiety in alcoholism in the withdrawal stage (author's transl)]". Munchener Medizinische Wochenschrift. 117 (35): 1387–1390. PMID241014.
^Tallone G, Ghirardi P, Bianchi MC, Ravaccia F, Bruni G, Loreti P (1980). "Reaction time to acoustic or visual stimuli after administration of camazepam and diazepam in man". Arzneimittel-Forschung. 30 (6): 1021–1024. PMID6106497.
^Morino A, Sasaki H, Mukai H, Sugiyama M (June 1986). "Receptor-mediated model relating anticonvulsant effect to brain levels of camazepam in the presence of its active metabolites". Journal of Pharmacokinetics and Biopharmaceutics. 14 (3): 309–321. doi:10.1007/BF01106709. PMID2878071. S2CID28921744.
^Ferrillo F, Balestra V, Carta F, Nuvoli G, Pintus C, Rosadini G (1984). "Comparison between the central effects of camazepam and temazepam. Computerized analysis of sleep recordings". Neuropsychobiology. 11 (1): 72–76. doi:10.1159/000118055. PMID6146112.
^Morino A, Nakamura A, Nakanishi K, Tatewaki N, Sugiyama M (December 1985). "Species differences in the disposition and metabolism of camazepam". Xenobiotica; the Fate of Foreign Compounds in Biological Systems. 15 (12): 1033–1043. doi:10.3109/00498258509049098. PMID2868575.
^Riva R, Albani F, Baruzzi A (January 1982). "Quantitative determination of camazepam and its metabolite temazepam in man by gas-liquid chromatography with electron-capture detection". Il Farmaco; Edizione Pratica. 37 (1): 15–19. PMID6120096.
^Legheand J, Cuisinaud G, Bernard N, Riotte M, Sassard J (1982). "Pharmacokinetics of intravenous camazepam in dogs". Arzneimittel-Forschung. 32 (7): 752–756. PMID6127087.
^Stricker BH (May 1984). "[Skin disorders caused by the use of camazepam (Albego)]". Nederlands Tijdschrift voor Geneeskunde. 128 (18): 870–872. PMID6145108.
^Schmitt EJ, Rochels R, Beck D, Mauersberg L (December 1980). "[Visual perception under the influence of a tranquilizer (author's transl)]". Klinische Monatsblätter für Augenheilkunde. 177 (6): 875–877. doi:10.1055/s-2008-1057748. PMID6110803. S2CID260193671.