Dysmenorrhea is defined as cramping pain in the lower abdomen occurring just before or during menstruation. Non-steroidal anti-inflammatory drugs (NSAIDs) are the mainstay of treatment, with the addition of oral contraceptive pills when necessary. With the widespread availability of over-the-counter NSAIDs, it is often assumed that women are treating themselves adequately. Unfortunately, this is not always the case. Therefore we evaluated the use of drugs for treating primary dysmenorrhea in Mexican students. A multiple-choice questionnaire was administered to 285 psychology students (20.6 +/- 2.4 yrs; range, 17-33 yrs), to assess the prevalence of dysmenorrhea and medications employed. The reported prevalence of dysmenorrhea among these women was 67%. Dysmenorrhea was mild in 34% moderate in 43% and severe in 21%. Of the dysmenorrheic sample, only 33.5% consulted physician in 2.6 +/- 0.2 cycles per year for their problem and the most common prescriptions were an over-the-counter medication with paracetamol pamabrom and pyrilamine maleate (Syncol; 22.4%) naproxen (18.4%), metamizole plus butylhyoscine bromide (10.2%), ibuprofen (6.1%) and butylhyoscine bromide (6.1%). On the other hand, self-medication was practiced by 64.9% of the women with dysmenorrhea in 6.1 +/- 3.8 cycles per year and the most common drugs by self-medication were Syncol (35.5%), naproxen (16.9%), metamizole plus naproxen butylhyoscine bromide (13.7%), an over-the-counter medication with adiphenine and propyphenazon (Espasmo-cibalgina; 10.5%), paracetamol (5.6%) butylhyoscine alone (4%) and ibuprofen (4%). Our data suggest that dysmenorrheic women use numerous drugs by self-medication for pain but infrequently accessed formal medical care.