SSRI (SSRIs) in the menopause

• selective serotonin and noradrenaline reuptake inhibitors (SSRIs & SNRIs) (1)
  
  • SSRIs as an alternative to HRT - general principles
    • in general baseline effectiveness 20-50%
    • class effect of SSRIs are of antidepressant benefit and improved quality of life
    • class effect of SSRIs include initial side effects such as nausea, dizziness, shortterm aggravation of base-line anxiety and mood, so encourage your patient to persevere and if necessary take on alternative days, even ½ tablet
    • class effect of all SSRIs is sexual dysfunction- no one SSRI is better than any other in this respect and there is great individual variation in response
    • some SSRIs (paroxetine, fluoxetine, paroxetine, sertraline) interact with cytochrome P450, so avoid in patients on Tamoxifen
      
      
  • SSRI’s such as paroxetine (12.5-25mg daily) has shown to reduce flushes in 50%, while fluoxetine (20mg daily) has also been reported to reduce in 60% (2) (1)
    • paroxetine
• dosage 10-20mg - baseline improvement 50-60%. Paroxetine has best evidence for vaso-motor control and has maximal benefit achieved at 10mg
• class effect of SSRIs are of antidepressant benefit and improved quality of life
• interacts with enzyme cytochrome P450 (CYN10) thereby rendering Tamoxifen less effective
  
  
  • fluoxetine (1)
    • dosage 20mg - baseline effectiveness 10-20mg
    • class effect of SSRIs are of antidepressant benefit and improved quality of life
    • like Paroxetine should be avoided in patients taking Tamoxifen
      
      
  • citalopram (Escitalopram) (1)
    • dosage 20mg - baseline benefit 40-50%
    • class effect of SSRIs are of antidepressant benefit and improved quality of life
    • much less effect on enzyme cytochrome P450 so can be used in patients on Tamoxifen
      
      
  • sertraline (1)
    • dosage 25-50mg - baseline benefit - little information
    • sertraline is the best anti-anxiety SSRI
    • least well tolerated with an increase in anxiety at the outset. Interacts with cytochrome P450, so avoid in patients on Tamoxifen

• SNRIs (venlafaxine) (1) - dosage 37.5mg -150mg sustained release preparations recommended; baseline benefit quoted 20-66%
  • often poorly tolerated at outset with dizziness and other associated SSRI side effects including sexual dysfunction, slow titration may be the answer
  • no interaction with cytochrome P450 so may be safest choice for patients on Tamoxifen

Notes (3):

• Finding Lasting Answers for Symptoms and Health (i.e., MsFLASH) studies revealed a significant reduction in hot flashes of 54% for escitalopram, 48% for estradiol, and 49% for venlafaxine
  • sexual desire was minimally better with estradiol than SSRI treatment, while venlafaxine was better than estradiol for therapy of anorgasmia, pain, and vaginal dryness
  • improvement in sleep quality and duration was minimally and equally improved with both forms of therapy
    
• in a separate study, paroxetine 7.5 mg daily was shown to improve hot flashes without weight gain or sexual dysfunction

Reference:

• (1) British Menopause Society. Prescribable alternatives to HRT (Accessed 12/2/2020).
• (2) Grady D. Clinical practice. Management of menopausal symptoms. N Engl J Med. 2006;355(22):2338-47.
• (3) Cobin RH, Goodman NF, on behalf of the AACE Reproductive Endocrinology Scientific Committee. American Association of Clinical Endocrinologists and American College of Endocrinology Position Statement on Menopause - 2017.