From the Guidelines
For an 83-year-old patient already on fluoxetine and estrogen who continues to experience hot flashes, gabapentin would be the best additional medication to consider. This recommendation is based on the evidence from a study published in the Annals of Oncology in 2008 1, which suggests that gabapentin may be at least as effective as SSRI/SNRIs in reducing hot flashes, with the added benefit of having no known drug interactions and not causing sexual dysfunction.
Key Points to Consider
- Gabapentin has been shown to reduce hot flashes by 51% compared to 26% on placebo in women with spontaneous menopausal symptoms 1.
- The recommended starting dose is 100-300 mg at bedtime, which can be gradually increased to 300 mg three times daily as needed and tolerated.
- It is essential to monitor for side effects such as dizziness, drowsiness, and unsteadiness, which can increase fall risk in elderly patients.
- Before starting gabapentin, kidney function should be assessed as dose adjustments may be needed in renal impairment, which is common in elderly patients.
- Regular follow-up every 2-4 weeks initially is recommended to evaluate efficacy and tolerability.
Benefits of Gabapentin
- Rapid onset of action, reducing hot flashes from 8.5 to 4.5/day over 4 weeks 1.
- Equivalent efficacy to estrogen in the treatment of hot flashes, although this study had a small sample size 1.
- Well-tolerated, with side effects such as dizziness, unsteadiness, and drowsiness improving after the first week of treatment and largely resolving by week 4 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Treatment Options for Hot Flashes
The patient is already taking fluoxetine, an SSRI, and estrogen for presumed post-menopausal symptoms. Considering additional medication for hot flashes, the following options can be explored:
- Venlafaxine: A serotonin-norepinephrine reuptake inhibitor (SNRI) that has been shown to decrease hot flashes by about 60% 2. It is a viable option for patients who are unable or unwilling to use hormone therapy.
- Gabapentin: A drug that appears promising as therapy for women unable or unwilling to use estrogen, with studies showing a decrease in hot flashes by 35% to 38% compared to placebo 3.
- Other SSRIs: Such as escitalopram and paroxetine, which have been found to have higher efficacy and safety in the treatment of menopausal hot flashes compared to other drugs in their class 4, 5.
Considerations
When selecting an additional medication, it is essential to consider the patient's medical history, current medications, and potential interactions. The patient is already taking fluoxetine, so it is crucial to evaluate the safety and efficacy of adding another medication to their regimen.
Efficacy of Current Medication
Fluoxetine, the patient's current medication, has been shown to decrease hot flashes by 13% compared to placebo 3. While it may provide some relief, additional medication may be necessary to achieve optimal symptom management.
Potential Interactions
The patient is also taking estrogen, which may interact with other medications. It is essential to monitor the patient's response to any new medication and adjust the treatment plan as needed to minimize potential interactions and side effects.