Thirty women completed marihuana use diaries and Form T of the Moos Menstrual Distress Questionnaire (MDQ) every day for three consecutive menstrual cycles. A 99.1% response rate was obtained: 2715 of a possible 2741 diaries were returned. Women reported smoking an average of 1.4 (+/- 2.0) marihuana cigarettes per day (range for individuals: 7.3 [+/- 3.8] to 0.2 [+/- 0.4]). There was no significant covariance between daily marihuana smoking and menstrual cycle phase. The psychological MDQ factors reflecting negative affect, difficulty in concentration, behavior change and arousal also did not vary with menstrual cycle phase. The physiological MDQ factors of pain, autonomic reactions and water retention were significantly increased during the premenstrual and/or menstrual phases of the cycle. MDQ scores during the premenstruum and menstruation were generally very low. These data indicate that in the absence of severe premenstrual dysphoria, changes in drug use are not systematically related to phase of the menstrual cycle.