Dysmenorrhea or painful menstruation can be either primary, where there is no observable organic causes, or secondary to a specific pelvic pathology such as endometriosis, ovarian cysts or pelvic infection. The pain of dysmenorrhea is due to uterine cramping and local ischemia which is related to increased production and release of endometrial prostaglandins (PGE2 and PGF2 alpha) and leukotrienes of the 4 series. (1) In women with primary dysmenorrhea the plasma concentration of vasopressin is also elevated. (2) (The effect of vasopressin on uterine activity in nonpregnant women is about five times more pronounced than that of oxytocin, and it increases premenstrually.)
Primary dysmenorrhea occurs in a high percentage of young women only in ovulatory cycles and the pain is normally limited to the first 48 to 72 hours of menstruation. (1) In fact, dysmenorrhea is the most frequent gynecological problem in adolescent girls (the prevalence
is 80 to 90%). (3) Daily activities are frequently affected and it is the most common cause of regular absenteeism in young women. (4)
Dietary and Lifestyle Factors
A review of published studies found that exercise was generally linked to a reduction in the prevalence or severity of symptoms. (5) However, the reviewers stressed the need for better controlled studies to confirm this relationship. Smoking, and even exposure to environmental cigarette smoke, were linked to a higher prevalence of dysmenorrhea. (6-8) Attempting to lose weight is significantly associated with increased prevalence of menstrual irregularity and pain. (9) This finding was independent of body mass index.
A higher intake of marine n-3 fatty acids was correlated with milder menstrual pain in two studies. (10,11) A low-fat, vegetarian diet was associated with an increase in sex-hormone binding globulin and reductions in body weight, dysmenorrhea (duration and intensity) and premenstrual symptom duration. (12)
Key Herbs for Pain Management
Since primary dysmenorrhea usually only causes problems for 1 to 2 days each month, it makes sense to use herbs which can help to control the pain at these times. Treatment throughout the whole menstrual cycle is best reserved for severe cases only (see the appendix to this article).
Short-term treatment consists of uterine spasmolytics, analgesics, sedatives and herbs which decrease prostaglandin production. They can be given at the onset of menstruation. However, these remedies are usually more effective for severe pain when given prior to the onset of menstruation by a few days. High doses need to be recommended to control the acute symptoms.
* Uterine spasmolytics include wild yam, cramp bark and raspberry leaves. This last herb is spasmolytic in the non-gravid uterus.
* Corydalis is a useful analgesic for any abdominal pain and California poppy is another analgesic herb which can be used.
* The prostaglandin-decreasing herbs are not powerful analgesics, so it is best to start their use before menstruation. These include ginger, turmeric and willow bark.
Corydalis
The tuber of a number of species of Corydalis (C. ambigua, C. yanhusuo and C. turtschaninovii) has been used in Traditional Chinese Medicine and is known as Yanhusuo. Yanhusuo is used to relieve pain and to promote circulation and particularly to treat dysmenorrhea. Other indications include chest pain, epigastric pain, abdominal pain, post-partum abdominal pain, injuries due to impact, fractures, bruises, sprains, amenorrhea and blood stasis after childbirth. (13-15)
Corydalis contains many alkaloids, including tetrahydropalmatine (THP). (16) In vivo animal studies have indicated that Corydalis (dried herb and water extract) by oral administration, and the isolated alkaloids (including THP) by injection, have analgesic activity. (13,17) Blockade of dopaminergic receptors contributes to the analgesic activity of THP. (18)
In an uncontrolled clinical trial of 44 patients with dysmenorrhea, administration (route unknown) of an alkaloidal constituent of Corydalis, dehydrocorydaline (150 mg/day), brought great relief in 14 patients and a decrease in pain in another 18. Observed side effects included a reduction in menstrual flow, headaches and fatigue. (14) THP (route unknown) has also been used in uncontrolled trials in China for analgesic effect in dysmenorrhea, neuralgia, headache and diseases of the internal organs. (13)
Ginger
The rhizome of Zingiber officinale has been used in Western herbal medicine as a spasmolytic, anti-inflammatory and circulatory stimulant. Ginger tea was recommended for relief of dysmenorrhea, to improve circulation (19) and as a circulatory stimulant for amenorrhea due to cold. (20)
Ginger and its components exert an anti-inflammatory effect by inhibiting both the cyclo-oxygenase and lipoxygenase enzymes (which belong to the prostaglandin and leukotriene biosynthetic pathways respectively)--they are dual inhibitors of arachidonic acid metabolism. This has been suggested by in vitro studies. (21,22) Oral administration of ginger extract inhibited carrageenan-induced paw swelling in vivo. (23) This demonstrates anti-inflammatory activity.
One scientist postulated that because ginger is a thromboxane synthetase inhibitor, which activates endorphin receptors, it may also be an effective analgesic for dysmenorrhea. (24)
Raspberry Leaf
The leaves of Rubus idaeus have been used in traditional herbal therapy for a variety of conditions relating to the female reproductive tract, especially during pregnancy and to facilitate delivery. (25)
Raspberry leaf tea was also reported in a 1941 medical research paper as being "employed...with apparently satisfying clinical results, in severe cases of dysmenorrhea." (26) Pharmacological studies conducted at the same time suggest that raspberry leaf relaxes the toned non-pregnant uterus. (27) This action would be of benefit in the treatment of dysmenorrhea. Raspberry leaf is also useful for any associated diarrhea.
Raspberry leaf is better known for its ability to assist with childbirth. Pharmacological studies investigating raspberry leaf support the concept of a regulation of uterine contractions. (28)
Wild Yam
The root and rhizome of Dioscorea villosa was traditionally regarded as a powerful spasmolytic and has been used for the treatment of uterine and ovarian pain, including dysmenorrhea. (25)
Wild yam contains the steroidal saponin dioscin. (29) Steroidal saponins or their metabolites may exert estrogenic effects by binding with estrogen receptors of the hypothalamus, which are part of the negative feedback mechanism of estrogen control. In the premenopausal woman, interaction of these compounds with receptors in the hypothalamus or pituitary displaces estrogen from receptors and blocks estrogen feedback. The body determines that estrogen levels are lower than they really are and responds by increasing follicle stimulating hormone and hence, estrogen.
This potential estrogen modulating activity of wild yam could assist in relieving a relative excess of progesterone late in the menstrual cycle which may be an underlying or contributing factor in dysmenorrhea.
Cramp Bark and Black Haw
In addition to its spasmolytic activity, the bark of Viburnum opulus (cramp bark) is regarded as a uterine tonic.30 Cramp bark has been used traditionally to relieve cramps and spasm of all kinds, to treat uterine and ovarian pain, dysmenorrhea (19,25) and irregular uterine contractions. (30) Herbal texts indicate that cramp bark and wild yam have often been prescribed together. (25,31)
Experimental studies have shown that cramp bark extract and its constituents relax uterine muscle. (30) The related species black haw (Viburnum prunifolium) is also used for the same applications.
[FIGURE 1 OMITTED]
Improving Compliance in Dysmenorrhea
As mentioned above, in order to control the pain of dysmenorrhea high doses of herbs need to be taken over a relatively short term. Given that compliance by teenagers with liquid extracts of herbs can be poor and during dysmenorrhea the patient's digestive tract is more sensitive than normal, the rationale for an herbal tablet for dysmenorrhea containing substantial doses was obvious. The following herbal tablet (MediHerb Cramplex) was developed and tested in patients:
Corydalis tuber 5:1 extract 240mg
from Corydalis ambigua tuber 1.2 g
Raspberry leaf 4:1 extract 200mg
from Rubus idaeus leaf 800 mg
Wild yam root and rhizome 4:1 extract 200mg
from Dioscorea villosa root and rhizome 800 mg
Cramp bark stem bark 5:1 extract 160mg
from Viburnum opulus stem bark 800 mg
Ginger rhizome 6:1 extract 133.3mg
from Zingiber officinale rhizome 800 mg
