Dysmenorrhea

OTCs Today

Mary Warner

Dysmenorrhea, defined as painful menstruation or menstrual cramps, is a frequent problem among adolescents and young adult women, with up to 93% of adolescent girls being affected. Primary dysmenorrhea is associated with cramp-like lower abdominal pain at the time of menstruation in the absence of pelvic disease and usually develops within 6 to 12 months after menarche, generally affecting women during their teens and early 20s. It occurs only during ovulatory cycles and generally decreases in women older than 24 years. Because it is such a common complaint, pharmacists are often asked how to best treat the painful symptoms of dysmenorrhea.

Causes and symptoms

Primary dysmenorrhea occurs in women without any underlying medical conditions and can be diagnosed based on symptoms and a physical exam, while secondary dysmenorrhea is related to an underlying medical condition, such as endometriosis, fibroids, or pelvic inflammatory disease, and must be diagnosed with pelvic ultrasound or laparoscopy in addition to a physical exam.

Although the cause of primary dysmenorrhea is not fully understood, prostaglandin and leukotriene levels appear to contribute to its occurrence and severity. Prostaglandin levels are two to four times greater in women with dysmenorrhea than in women without dysmenorrhea, and leukotrienes are also elevated in women with dysmenorrhea. Because prostaglandins stimulate uterine contractions, the increased levels of prostaglandins in dysmenorrhea can lead to strong uterine contractions similar to those experienced during labor, as well as excessive vasoconstriction, resulting in uterine ischemia and pain.

The pain with primary dysmenorrhea is cyclical and starts the day before or the day of the start of menstruation, usually subsiding within 2 or 3 days. Pain is typically experienced as a continuous dull ache, with spasmodic cramping in the lower midabdominal or suprapubic region that may radiate to the lower back and upper thighs. The uterine contractions can force prostaglandins and leukotrienes into systemic circulation, causing additional symptoms such as nausea, vomiting, fatigue, dizziness, bloating, diarrhea, and headache. Pain from secondary dysmenorrhea usually begins earlier in the menstrual cycle and lasts longer than typical menstrual cramps.

Treating dysmenorrhea

Mild-to-moderate menstrual cramping is normal, but some people have such severe pain during their period that it interferes with their day-to-day life and prevents them from doing things they enjoy. Both nonpharmacological treatment and medication can help with painful periods.

Successful nonmedication treatment options for primary dysmenorrhea include heat, massaging the lower back and abdomen, avoiding foods and drinks that contain caffeine, and exercising regularly. Success with other options, such as dietary supplements (e.g., fish oil, fenugreek, ginger, valerian, vitamin B1, vitamin D, zataria, and zinc sulfate), yoga, acupuncture, and relaxation or breathing exercises, is unclear. Treatment of secondary dysmenorrhea involves treating the underlying medical condition. 

First-line medication options for treating primary dysmenorrhea include NSAIDs (e.g., aspirin, ibuprofen, and naproxen sodium), acetaminophen, and hormonal contraceptives, such as contraceptive pills, patches, or vaginal rings. All of these work by reducing the level of prostaglandins in the body. Aspirin and acetaminophen may be adequate for treating mild symptoms of dysmenorrhea, but they are less effective than nonsalicylate NSAIDs such as ibuprofen and naproxen sodium.

Treatment with nonsalicylate NSAIDs should begin at the onset of menses or pain, as the most prostaglandin is released during the first 2 to 3 days. If the pain relief is inadequate, treatment beginning 1 or 2 days before expected menses may improve symptomatic relief. Optimal pain relief is achieved when ibuprofen and naproxen sodium are taken on a schedule (every 4–6 hours for ibuprofen and every 8–12 hours for naproxen sodium) rather than on an as-needed basis.

Patients with dysmenorrhea may respond better to one NSAID than to another, so if the maximum nonprescription dosage of one medication does not provide adequate pain relief, switching to another agent is recommended. In addition, the analgesic effect plateaus with most NSAIDs, so dosage increases may cause adverse effects without providing additional benefit. If nonprescription NSAID therapy does not provide adequate pain relief, prescription NSAIDs, prescription dosages of nonprescription NSAIDs, and/or use of a hormonal contraceptive may be effective. In some cases, the use of a contraceptive and an NSAID may be needed for adequate symptom relief.

What to tell your patients

Menstrual cramps themselves usually don’t cause complications, other than disrupting daily life. However, patients should be advised to see their primary care provider if they experience severe dysmenorrhea, a change in the pattern or intensity of pain, or inadequate response or intolerance to NSAIDs for evaluation of prescription treatment options.

For further information, see the section on “Disorders Related to Menstruation” in APhA’s Handbook of Nonprescription Drugs, available in print on the APhA bookstore at pharmacist.com or online in APhA OTC on PharmacyLibrary (www.pharmacylibrary.com). ■