Can a premenopausal woman with hypoactive sexual desire disorder safely take Addyi (flibanserin) together with gabapentin?

Can You Take Addyi and Gabapentin Together?

Yes, you can safely take Addyi (flibanserin) and gabapentin together, as gabapentin has no known drug interactions and no absolute contraindications with other medications, making it compatible with flibanserin for a premenopausal woman with hypoactive sexual desire disorder. 1

Safety Profile of the Combination

The combination of flibanserin and gabapentin presents no documented pharmacokinetic or pharmacodynamic interactions:

• Gabapentin has no known drug interactions, which distinguishes it from SSRIs/SNRIs that can have significant interactions with other medications 1
• Gabapentin has no absolute contraindications, making it one of the safest options for concurrent use with other CNS-active medications 1
• Unlike SSRIs/SNRIs, gabapentin does not cause sexual dysfunction, which is particularly relevant when treating HSDD 1

Clinical Context for Each Medication

Flibanserin for HSDD

• Flibanserin 100 mg daily at bedtime is the FDA-approved first-line treatment for premenopausal women with HSDD 2, 3
• The efficacy is modest, resulting in approximately 0.5 to 1 additional satisfying sexual event per month (or about 1 additional event every 2 months) compared to placebo 2, 3, 4
• Common side effects include dizziness (10.5%), somnolence (11.8%), and fatigue (10.3%) 4

Gabapentin Indications

If gabapentin is being prescribed concurrently, the most likely clinical scenarios include:

• Neuropathic pain management, where gabapentin demonstrates good efficacy 1
• Menopausal hot flashes, where gabapentin reduces hot flashes by approximately 49-54% versus 21-31% with placebo 1
• Seizure disorders, though antiepileptic drugs like gabapentin can cause weight gain, which may indirectly affect reproductive endocrine function 1

Important Safety Considerations

Additive CNS Effects

While no direct drug interaction exists, both medications can cause CNS side effects:

• Monitor for additive sedation and dizziness, as both flibanserin and gabapentin can cause somnolence and dizziness 1, 4
• Gabapentin's side effects (dizziness, unsteadiness, drowsiness) affect up to 20% of patients but typically improve markedly after the first week and largely resolve by week 4 1
• Flibanserin must be taken at bedtime to minimize CNS side effects 2, 3

Timing Strategy

• Take flibanserin at bedtime as prescribed 2, 3
• Gabapentin dosing can be adjusted to minimize overlapping peak CNS effects if sedation becomes problematic 1
• Gabapentin has a rapid onset of action (less than 1 week), allowing quick assessment of tolerability 1

Common Pitfalls to Avoid

Alcohol Contraindication

• Avoid alcohol consumption with flibanserin, as this is a critical safety concern separate from the gabapentin interaction 5
• While one study showed co-administration with alcohol resulted in manageable adverse events, a significantly greater percentage of participants could not have standing blood pressure obtained when flibanserin was combined with higher alcohol doses 5

Weight Monitoring

• Gabapentin can cause weight gain, which may indirectly affect reproductive endocrine function and potentially worsen HSDD through insulin resistance mechanisms 1
• This is particularly relevant in women predisposed to polycystic ovary syndrome 1

Alternative Considerations

If gabapentin is being used for hot flashes and sexual dysfunction coexists:

• Gabapentin may be preferred over SSRIs/SNRIs specifically because it does not cause sexual dysfunction, making it more compatible with HSDD treatment goals 1
• There is no benefit to adding gabapentin to SSRIs/SNRIs for hot flash management 1

Monitoring Recommendations

• Assess for excessive sedation or dizziness during the first 1-4 weeks when gabapentin side effects are most prominent 1
• Monitor weight changes as gabapentin-related weight gain could theoretically impact HSDD outcomes 1
• Evaluate flibanserin efficacy at 4 weeks, as treatment is unlikely to be effective if no response is seen by this timepoint 1
• Reassess sexual function using validated measures (FSFI desire domain score, FSDS-R) to objectively track improvement 4, 6