IRCT2012080610517N1.

Trial name or title	Oral zinc sulfate for dysmenorrhoea in adolescent Iranian girls: a randomised double‐blind placebo‐controlled clinical trial.
Methods	RCT
Participants	Inclusion: history of regular menstrual cycles of 21 to 35 days with actual menstruation period of 3 to 7 days; if the participants experienced at least 4 consecutive painful menstruation periods in the past 6 months; the pain started 1 day before or at the starting day of menstruation and if dysmenorrhoea disturbed daily activity of the patients for at least 1 day per month. After describing the study protocol, an informed consent was taken from the participants' parents. Enrolled participants underwent pelvic ultrasonography examination by a gynaecologist. Exclusion: a clinically significant medical history or active disease; pelvic pathology diagnosed by the gynaecologist; used other medications or supplements; and uninterested in using the drug and filling the pain charts of the study.
Interventions	Group 1: intervention: 50 mg capsule of zinc sulphate, QD, for 3 months Group 2: placebo, using the same method as the intervention group. QD 1 capsule for 3 months
Outcomes	Pain duration. Timepoint: in 3 menstruation cycles in 3 months. Method of measurement: chart the day the participant has pain; pain severity. Timepoint: in 3 menstruation cycles in 3 months. Method of measurement: pain rating scale.
Starting date	02 September 2012
Contact information	Seyed Omid Reza Zekavat (ozekavat@gmail.com)
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