Table 4.

The effects of zinc supplementation on various clinical signs in women with primary dysmenorrhea (PD).

Type of Supplementation	Inclusion Criteria	Parameters	Placebo		Zinc			Ref.
			Baseline	End of Trial	Baseline	End of Trial	p Value
30 mg of zinc (zinc gluconate) 4 days per menstrual cycle	Women with PD 17 years Zinc group (n = 1)	Muscle pain			Yes	No		[87]
		Duration of menstrual bleeding			Normal	Normal
14 mg of zinc (zinc acetate) as throat lozenges 2 days prior to and 1st day of menstrual cycle; 9 × day (total daily dose 126 mg)	Women with PD 23 years Zinc group (n = 1)	Muscle pain			Yes	No
		Menstrual cramp			Yes	No
		Duration of menstrual bleeding			Normal	Normal
60 mg of zinc (zinc gluconate) 3–4 days per menstrual cycle; twice a day per 3 cycles	Women with PD 49 years Zinc group (n = 1)	Muscle pain			Yes	No
		Menstrual cramp			Yes	No
		Duration of menstrual bleeding			Long (8–9 days)	Normal (5 days)
30 mg of zinc 1–2 days per menstrual cycle;	Women with PD 30 years Zinc group (n = 1)	Muscle pain			Yes	No
		Menstrual cramp			Yes	No
		Duration of menstrual bleeding			Normal	Normal
30 mg of zinc 3–5 days per menstrual cycle; 10 years	Women with PD 38 years Zinc group (n = 1)	Muscle pain			Yes	No
		Menstrual cramp			Yes	No
		Duration of menstrual bleeding			Normal	Normal
90 mg of zinc (220 mg of zinc sulfate) 4 days—from the day before to the third day of menstrual bleeding per 2 cycles	Women with PD 15–18 years Zinc group (n = 56) Control group – placebo (n = 46) Randomized Placebo-Controlled Trial	PVAS						[88]
		Severity of dysmenorrhea	7.76 ± 1.30		8.01 ± 1.12
		1st cycle		7.13 ± 1.30		6.18 ± 1.70	<0.001
		2nd cycle		6.95 ± 1.67		3.12 ± 1.2	<0.001
		Diarrhea
		1st cycle		1 (2.2)*		1 (1.9)
		2nd cycle		1 (2.4)*		2 (3.8)
		Headache
		1st cycle				1 (1.19)*
		2nd cycle
		Heartburn
		1st cycle		1 (2.2)*		1 (1.19)*
		2nd cycle		1 (2.4)*		1 (1.19)*
		Duration of menstrual bleeding	6.1 ± 1.02		6.7 ± 1.14
20 mg of zinc (50 mg of zinc sulfate) 4 days—from the first day to next three days of menstrual bleeding per 3 cycles	Women with PD 14–18 years Zinc group (n = 60) Control group—placebo (n = 60) DBRCT	VAS						[89]
		Pain duration			5.47 ± 1.32
		1st cycle		4.62 ± 2.02		3.95 ± 1.52	<0.05
		2nd cycle		4.43 ± 1.76		3.22 ± 1.35	<0.001
		3rd cycle		4.42 ± 1.73		2.77 ± 1.47	<0.001
		Pain severity			7.30 ± 2.43
		1st cycle		6.96 ± 1.56		6.60 ± 3.79
		2nd cycle		6.68 ± 1.79		5.01 ± 1.70	<0.001
		3rd cycle		6.58 ± 1.60		4.23 ± 1.69	<0.001
50 mg of zinc 4 days—before the menstruation twice a day per cycle	Women with PD 14–18 years Zinc group (n = 34) Control group—placebo (n = 32) DBRCT	VAS						[90]
		Severity of bleeding	81.2 ± 71.2	78.9 ± 60.5	78.2 ± 54.1	64.3 ± 32.5	<0.05
		Severity of dysmenorrhea	56.3 ± 15.0	54.5 ± 18.1	64.9 ± 16.2	41.5 ± 22.3	<0.01
		Muscular pain	23*	22*	27*	20*	<0.03
		Disability in daily activities	29*	26*	27*	10*	<0.001
		Weakness	26*	21*	33*	26*	<0.02
90 mg of zinc (220 mg of zinc sulfate) and 250 mg of mefenamic acid 6 days—three days before and three days after menstruation per 3 cycles	Women with PD 18–26 years Zinc group and mefenamic acid (n = 100) Control group—placebo and mefenamic acid (n = 100) DBRCT	VAS						[91]
		Mean pain	5.8 ± 2.1	2.9 ± 2.6	5.3 ± 1.8	1.2 ± 1.9	<0.001
		Dysmenorrhea
		Yes		67*		36*	<0.001
30 mg of zinc 2 days before—and continuing until prior to the end of menstrual bleeding twice a day per 3 cycles.	Women with PD 17–25 years Zinc group (n = 34)	VAS						[92]
		Menstrual pain			4.92 ± 1.80
		1st cycle				3.37 ± 2.04	<0.001
		2nd cycle				3.30 ± 1.93	<0.001
		3rd cycle				2.70 ± 2.03	<0.001

Values are given as mean ± SD; * values are given as a %; DBCT: double-binding randomized clinical trial; PVAS: pain visual analog scale; VAS: visual analog scale.