Until now, no reliable biological markers of risk and relapse in cocaine-dependent patients have been identified. The yawn-inducing Apomorphine test has been proposed as a marker for predicting relapse during cocaine withdrawal.

Studying the Apomorphine complete Test as a predictor of relapse in intranasal cocaine dependet-patients during abstinence.

39 (35 men) cocaine addicts were recruited and included in an addiction program involving 2 weeks in-patient setting and a 23 follow-up weeks. Dependence was diagnosed according to DSM-IV-TR criteria and other axis I comorbid main diagnosis were excluded.

We performed the Apomorphine complete Test (including an Apomorphine Test plus a Placebo Test) at the beginning (day 1) and end (day 11 or 12) of a detoxification program. Patient received 0′005 mg/kg of apomorphine and 0′005 mg/kg of placebo subcutaneously each test.

The patients who relapse prematurely (before 4 weeks), yawn more 11′42 (0–31) in the Apomorphine complete Test realized the first day of the detoxification compared with patients that relapse no prematurely (after 4 weeks of follow-up), 6′83 (0–20), Z -2′14 p < 0′03. A model can establish, with a point of court of 7 yawns in the first Apomorphine complete Test that has a sensibility of 61 ′ 9% and a specificity of 70 ′ 6%.

There an increased number of yawns in relapse-patients The Apomorphine complete Test could be proposed as a biological marker of early relapse.