Management of Premenstrual Syndrome (PMS)
For women with PMS, initiate calcium carbonate 1200 mg daily as first-line therapy, and reserve SSRIs (fluoxetine, sertraline, or paroxetine) for those with severe mood symptoms or who fail calcium supplementation. 1
Diagnostic Confirmation Required First
Before initiating treatment, confirm the diagnosis by having the patient prospectively track symptoms using the Daily Record of Severity of Problems for at least two menstrual cycles. 2 The key diagnostic feature is symptom occurrence exclusively during the luteal phase (two weeks before menstruation) with complete resolution within a few days of menstruation onset, followed by a mandatory symptom-free period in the follicular phase. 3, 2
Treatment Algorithm
Step 1: First-Line Pharmacologic Therapy
Calcium carbonate 1200 mg daily is the evidence-based first-line treatment for mild-to-moderate PMS based on level I evidence. 1 This should be taken continuously throughout the menstrual cycle, not just during the luteal phase.
Step 2: Lifestyle Modifications (Concurrent with Pharmacotherapy)
While evidence is inconclusive for lifestyle changes alone, implement these measures given their overall health benefits and no harm profile: 1
- Dietary modifications: Reduce caffeine, alcohol, and salt intake; increase complex carbohydrates 1
- Regular aerobic exercise: At least 30 minutes most days of the week 1
- Stress reduction techniques: Cognitive behavioral therapy or relaxation strategies 1
Step 3: SSRIs for Moderate-to-Severe or Refractory Cases
For women with severe affective symptoms (PMDD) or those who fail calcium therapy, initiate SSRIs as they reduce overall premenstrual symptoms with moderate-certainty evidence (SMD -0.57). 4
SSRI Dosing Strategy:
Continuous administration is more effective than luteal-phase-only dosing (SMD -0.69 vs -0.39, p=0.03 for subgroup difference). 4 Choose one of:
- Fluoxetine 20 mg daily continuously 4
- Sertraline 50-150 mg daily continuously 4
- Paroxetine 10-30 mg daily continuously 4
- Citalopram or escitalopram at standard doses 4
Step 4: Adjunctive Therapies for Specific Symptoms
Spironolactone can be considered for bloating and fluid retention, though evidence is inconclusive. 1 Use 25-100 mg daily during the luteal phase only.
NSAIDs (such as mefenamic acid) may help physical symptoms like cramping, though evidence remains unproven. 5, 1
Critical Counseling About SSRI Adverse Effects
Patients must be informed that SSRIs significantly increase risk of specific adverse effects with the following approximate numbers needed to harm (NNTH): 4
- Nausea: OR 3.30 - most common side effect 4
- Sexual dysfunction/decreased libido: OR 2.32 4
- Insomnia: OR 1.99 4
- Asthenia/decreased energy: OR 3.28 4
- Somnolence/decreased concentration: OR 3.26 4
- Tremor: OR 5.38 4
These effects occur with moderate certainty and should be weighed against symptom severity when making treatment decisions.
Treatments to Avoid
Do NOT prescribe progesterone - it has been proven ineffective in multiple controlled trials despite widespread historical use. 5, 1
Bromocriptine is ineffective and should not be used. 1
Evening primrose oil and vitamin B6 have inconclusive evidence and cannot be recommended as primary therapy, though they may be tried as adjuncts given low harm potential. 1
Common Pitfalls
Avoid treating without prospective symptom documentation - retrospective recall is unreliable and leads to misdiagnosis. 2 Many women attribute symptoms to PMS that occur throughout the cycle.
Do not start with progesterone or oral contraceptives as first-line therapy - despite their popularity, evidence for standard combined oral contraceptives in PMS is inconclusive. 1 Calcium and SSRIs have superior evidence.
Recognize that 68% of SSRI studies were pharmaceutical-funded, which may overestimate benefits, so interpret efficacy claims cautiously and prioritize patient-reported outcomes. 4