Current Scheduling Status
Year(s) and type of review / ECDD meetings
Drug Class
Recommendation (from TRS)
Substance identification
Mesocarb (CAS 34262-84-5), chemically 3-(a-methylphenethyl)-N-(phenylcarbamoyl)sydnone imine, is also known as Pharmanocarb, Sidnocarb and Sydnocarb. Mesocarb has one asymmetric carbon atom, so two stereoisomeric forms and one racemate are possible.
WHO review history
In 1992, the 28th meeting (6) of the Committee recommended a critical review of mesocarb if positive results were obtained from dependence studies which had been arranged. These test results were made available, and the Committee decided to conduct a critical review.
Similarity to known substances and effects on the CNS
Chemically, mesocarb is a sydnone imine having an amfetamine-like
moiety in its molecule. Of the two stereoisomers of mesocarb, only the
laevorotatory isomer exerts a stimulant effect on the central nervous
system, which is significantly weaker than that of dexamfetamine.
Mesocarb produces locomotor stimulation, anorectic activity, enhancement of conditioned reflexes, and shortening of the period of action of hypnotic agents. Mesocarb has been reported to increase work capacity and improve cardiovascular function without requiring above-normal oxygen consumption. Its adverse reactions are similar to those of other central nervous system stimulants. Several studies in humans have shown that mesocarb increases resistance to environmental stresses, such as cold temperature, low gravity and low oxygen levels. In addition, there are several pharmacological studies in animals of mesocarb used in combination with other substances, such as a mesocarb-acetylsalicylic acid combination.
Dependence potential
Drug discrimination studies in animals indicate that mesocarb generalizes to central nervous system stimulants such as dexamfetamine and cocaine. It also has some reinforcing effects in monkeys, suggesting a low to moderate dependence potential.
Actual abuse and or/evidence of likelihood of abuse
There is some evidence to indicate that mesocarb is abused in sports, and its use has been banned by the International Olympic Committee. Information from the International Narcotics Control Board (INCB) indicates that large quantities of a pharmaceutical preparation containing mesocarb and acetylsalicylic acid have been illegally exported to West Africa, though this has been reportedly discontinued. Although epidemiological data are not available, it is believed that most if not all of the exported combination product was abused. On the basis of available information, mesocarb is assessed to have an appreciable abuse liability.
Therapeutic usefulness
Mesocarb is used in several countries, mainly in eastern Europe, as a stimulant to counteract acute intoxication by depressants, for the treatment of hyperactivity and nocturnal enuresis in children and as an "energizer" to enhance resistance to environmental stress. The therapeutic usefulness of mesocarb is estimated to be between little and moderate.
Recommendation
Although no epidemiological data are available on health problems associated with the abuse of mesocarb, there is evidence that mesocarb is abused in sports, and illicit activities involving mesocarb have been reported. On the basis of this and the available data concerning its pharmacological and toxicological profile, dependence potential and likelihood of abuse, the public health and social problems associated with the abuse of mesocarb are assessed to be significant. On the basis of this and the assessment of its therapeutic usefulness, it is recommended that mesocarb be placed in Schedule IV of the Convention on Psychotropic Substances, 1971.
Mesocarb (CAS 34262-84-5), chemically 3-(a-methylphenethyl)-N-(phenylcarbamoyl)sydnone imine, is also known as Pharmanocarb, Sidnocarb and Sydnocarb. Mesocarb has one asymmetric carbon atom, so two stereoisomeric forms and one racemate are possible.
WHO review history
In 1992, the 28th meeting (6) of the Committee recommended a critical review of mesocarb if positive results were obtained from dependence studies which had been arranged. These test results were made available, and the Committee decided to conduct a critical review.
Similarity to known substances and effects on the CNS
Chemically, mesocarb is a sydnone imine having an amfetamine-like
moiety in its molecule. Of the two stereoisomers of mesocarb, only the
laevorotatory isomer exerts a stimulant effect on the central nervous
system, which is significantly weaker than that of dexamfetamine.
Mesocarb produces locomotor stimulation, anorectic activity, enhancement of conditioned reflexes, and shortening of the period of action of hypnotic agents. Mesocarb has been reported to increase work capacity and improve cardiovascular function without requiring above-normal oxygen consumption. Its adverse reactions are similar to those of other central nervous system stimulants. Several studies in humans have shown that mesocarb increases resistance to environmental stresses, such as cold temperature, low gravity and low oxygen levels. In addition, there are several pharmacological studies in animals of mesocarb used in combination with other substances, such as a mesocarb-acetylsalicylic acid combination.
Dependence potential
Drug discrimination studies in animals indicate that mesocarb generalizes to central nervous system stimulants such as dexamfetamine and cocaine. It also has some reinforcing effects in monkeys, suggesting a low to moderate dependence potential.
Actual abuse and or/evidence of likelihood of abuse
There is some evidence to indicate that mesocarb is abused in sports, and its use has been banned by the International Olympic Committee. Information from the International Narcotics Control Board (INCB) indicates that large quantities of a pharmaceutical preparation containing mesocarb and acetylsalicylic acid have been illegally exported to West Africa, though this has been reportedly discontinued. Although epidemiological data are not available, it is believed that most if not all of the exported combination product was abused. On the basis of available information, mesocarb is assessed to have an appreciable abuse liability.
Therapeutic usefulness
Mesocarb is used in several countries, mainly in eastern Europe, as a stimulant to counteract acute intoxication by depressants, for the treatment of hyperactivity and nocturnal enuresis in children and as an "energizer" to enhance resistance to environmental stress. The therapeutic usefulness of mesocarb is estimated to be between little and moderate.
Recommendation
Although no epidemiological data are available on health problems associated with the abuse of mesocarb, there is evidence that mesocarb is abused in sports, and illicit activities involving mesocarb have been reported. On the basis of this and the available data concerning its pharmacological and toxicological profile, dependence potential and likelihood of abuse, the public health and social problems associated with the abuse of mesocarb are assessed to be significant. On the basis of this and the assessment of its therapeutic usefulness, it is recommended that mesocarb be placed in Schedule IV of the Convention on Psychotropic Substances, 1971.
ECDD Recommendation
Inclusion in Schedule IV of the 1971 Convention on Psychotropic Substances
Link to full TRS
who_trs_856.pdf1.07 MB