Can psychiatric symptoms be induced by Antabus (disulfiram) or Dipsan (calcium carbimide)? Are any

Fråga: Can psychiatric symptoms be induced by Antabus (disulfiram) or Dipsan (calcium carbimide)? Are any kinetic reactions with neuroleptics known? The question comes from a case where the dose titration of neuroleptics is difficult in a man with a schizoaffective disorder. AT Disulfiram inhibits aldehyde dehydrogenase, which in the CNS catalyses the conversion of dopamine to homovanillic acid, and also inhibits dopamine-betahydroxylase which converts dopamine to noradrenaline. A number of disulfiram-associated psychotic reactions in patients with no other medication has been described, where the symptoms were related to an increased dopamine concentration and a decreased noradrenaline concentration in the CNS (1). The syndrome includes disorientation and impaired memory, abnormal EEG with diffuse slowing or accentuation of already existing abnormalities, ataxia, somnolence and a psychotic state with hallucinations, paranoic delusions and emotional lability (2). The psychiatric condition has been compared with that seen after an LSDintoxication. The time of onset varies from days to months and the syndrome has in most cases resolved within a few days to a few weeks after withdrawal (1). Neuroleptics have a limited effect on the symptoms and might even worsen them (3). The incidence of psychotic reactions has been reported to vary from between 2 and 20 per cent, but these figures are based on old reports with higher doses than are used today (4). However, many more recent reports concern daily doses of only 250 mg. A clinical diagnosis of schizophrenia and low concentrations of dopamine betahydroxylase seem to predispose one to these adverse reactions. We have found no reports about kinetic interactions between disulfiram and neuroleptics but this possibility does not seem to have been systematically investigated. No reports of psychic adverse events during treatment with calcium carbimide have been found, but information is incomplete (5). Since calcium carbimide does not inhibit microsomal oxidases, interactions with neuroleptics would not be expected. Three cases of psychic adverse events in connection with disulfiram have been reported to SADRAC (Swedish Adverse Drug Reactions Advisory Committee), none of which concerned calcium carbimide. The three reports concerned depression, confusion and hallucinations, respectively.

Sammanfattning: Disulfiram has been reported to be able to induce reversible psychotic symptoms and affective disturbances with a low frequency. The probable mechanism is a blockade of dopamine metabolising enzymes. The information about the side-effects of calcium carbimide is limited, but no CNS symptoms have been reported. Neither of the two drugs has been shown to alter the kinetics of neuroleptics.

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