Urinary cyclic AMP excretion by methadone subjects during gradual and acute withdrawal.

Laboratory and animal investigations have supported the hypothesis that levels of cyclic AMP are stable during tolerance to narcotic drugs and increased during withdrawal. In order to test this hypothesis, serial 24-h urinary excretion of cyclic AMP by long-term methadone addicts was determined during a period of stable methadone intake, a period of gradual withdrawal, and a period of acute withdrawal. Cyclic AMP excretion during stable methadone intake is identical to that of normal control subjects. Neither gradual nor acute withdrawal appears to affect the urinary excretion of cyclic AMP. These data agree with previous reports in the literature which suggest that cyclic AMP levels are not altered during tolerance to narcotics, but do not support the hypothesis that levels of the nucleotide might be increased during withdrawal.