Flibanserin represents a significant advancement in the pharmacological management of acquired, generalized hypoactive sexual desire disorder (HSDD) in premenopausal women. As a multifunctional serotonin agonist and antagonist (MSAA), it operates through a novel central mechanism rather than a hormonal pathway, distinguishing it from previous therapeutic approaches. This non-hormonal, daily oral medication is specifically indicated for premenopausal women experiencing distress due to low sexual desire, offering a targeted neurochemical intervention that addresses the complex biopsychosocial nature of female sexual dysfunction. Its approval marked a pivotal moment in women’s sexual health, providing a clinically validated option for a condition that was previously underserved by pharmacotherapy.

Features

• Active ingredient: Flibanserin 100 mg
• Pharmacologic class: Multifunctional serotonin agonist and antagonist (MSAA)
• Administration: Oral tablet, taken once daily at bedtime
• Mechanism of action: Acts centrally as a postsynaptic 5-HT1A receptor agonist and a presynaptic 5-HT2A receptor antagonist
• Prescription status: Available by prescription only, following a thorough benefit-risk evaluation by a healthcare provider
• Packaging: Supplied in bottles or blister packs, with clear patient instructions included

Benefits

• Increases the number of satisfying sexual events (SSEs) per month
• Reduces distress associated with low sexual desire, as measured by validated patient-reported outcome tools
• Offers a non-hormonal treatment pathway, making it suitable for women who cannot or prefer not to use hormone-based therapies
• Provides a daily regimen that integrates simply into a patient’s routine, taken at bedtime to mitigate potential side effects like somnolence
• Addresses the neurochemical underpinnings of desire regulation, offering a mechanism distinct from previous therapies focused solely on arousal or orgasm
• Supported by robust clinical trial data demonstrating statistically significant improvement over placebo in premenopausal women with HSDD

Common use

Flibanserin is indicated for the treatment of premenopausal women with acquired, generalized hypoactive sexual desire disorder (HSDD). HSDD is characterized by a persistent or recurrent deficiency or absence of sexual fantasies and desire for sexual activity, causing marked distress or interpersonal difficulty. The condition must be acquired (i.e., developing in a patient who previously had no such issues) and generalized (not situational or partner-specific). It is not intended for use in postmenopausal women or in men, and its use should be considered only after other potential contributing factors—such as relationship issues, comorbid medical conditions, or concomitant medications that may suppress libido—have been addressed. Diagnosis should be made using appropriate diagnostic criteria and patient history.

Dosage and direction

The recommended dosage of flibanserin is 100 mg taken orally once daily, at bedtime. Administration at bedtime is advised to mitigate the risks of hypotension, syncope, and central nervous system depression (such as somnolence and sedation), which are potential side effects. The medication should be swallowed whole with water and not crushed or chewed. It may be taken with or without food, though consistency in administration is recommended. Dose titration is not typically required, and the 100 mg dose is the only strength indicated for therapeutic use. Patients should be advised not to increase the dose or frequency without consulting their healthcare provider. If a dose is missed at bedtime, it should be skipped; the next dose should be taken at the usual time the following evening. Doubling up on doses is not recommended.

Precautions

Prior to initiating treatment with flibanserin, healthcare providers should conduct a thorough assessment of the patient’s medical history, with particular attention to conditions that may increase susceptibility to adverse effects. Caution is advised in patients with a history of hypotension, syncope, cardiovascular disease, hepatic impairment, or depression. Alcohol consumption is contraindicated due to the risk of severe hypotension and syncope. Patients should be advised to avoid activities requiring full alertness, such as driving or operating machinery, until they know how the medication affects them, especially during the initial treatment period. Concomitant use with moderate or strong CYP3A4 inhibitors is contraindicated. Patients should be monitored for signs of somnolence, dizziness, or hypotension, and advised to report any fainting episodes or unusual symptoms promptly.

Contraindications

Flibanserin is contraindicated in the following scenarios: concomitant consumption of alcohol; use with moderate or strong CYP3A4 inhibitors (e.g., ketoconazole, fluconazole, erythromycin, verapamil); hepatic impairment (Child-Pugh Class B or C); and in patients with a known hypersensitivity to flibanserin or any of its excipients. It is also not indicated for use in postmenopausal women or in men. Concomitant use with other CNS depressants may potentiate sedation and hypotension and should be approached with extreme caution, if used at all.

Possible side effects

The most commonly reported adverse reactions associated with flibanserin include dizziness, somnolence, nausea, fatigue, insomnia, and dry mouth. Syncope and hypotension were observed in clinical trials, particularly in association with alcohol use or concomitant CYP3A4 inhibitors. Less common side effects may include anxiety, flushing, and abdominal pain. Patients should be counseled on the potential for these effects and advised on strategies to manage them, such as taking the medication at bedtime to minimize daytime drowsiness. Any severe or persistent symptoms should be reported to a healthcare provider for evaluation.

Drug interaction

Flibanserin is primarily metabolized by CYP3A4 and, to a lesser extent, by CYP2C19. Its pharmacokinetics are significantly affected by inhibitors and inducers of these enzymes. Concomitant use with moderate or strong CYP3A4 inhibitors is contraindicated due to the risk of substantially increased flibanserin exposure and potentiated adverse effects such as hypotension and syncope. Concomitant use with CYP3A4 inducers (e.g., rifampin, carbamazepine) may reduce flibanserin efficacy. Use with other CNS depressants (e.g., benzodiazepines, opioids, sedating antihistamines) may enhance sedative effects and should be avoided or closely monitored. Flibanserin itself is a weak CYP3A4 inhibitor and may increase concentrations of drugs metabolized by this pathway; caution is advised with narrow therapeutic index drugs.

Missed dose

If a dose of flibanserin is missed at the usual bedtime, the patient should skip the missed dose and resume the regular dosing schedule the following evening. Taking two doses close together (double-dosing) is not recommended, as it may increase the risk of adverse effects such as hypotension, syncope, and somnolence. Patients should be advised to maintain a consistent dosing routine and to use reminders if necessary to support adherence.

Overdose

In the event of a suspected overdose, medical attention should be sought immediately. Symptoms of overdose may include severe hypotension, syncope, profound sedation, or other signs of excessive CNS depression. There is no specific antidote for flibanserin overdose. Management should be supportive and symptomatic, including monitoring of vital signs (particularly blood pressure and heart rate) and providing appropriate interventions such as intravenous fluids for hypotension. Gastric lavage or administration of activated charcoal may be considered if ingestion was recent, though the rapid absorption of flibanserin may limit utility.

Storage

Flibanserin tablets should be stored at room temperature, between 20°C and 25°C (68°F and 77°F), in a dry place protected from light and moisture. The medication should be kept in its original container, tightly closed, and out of reach of children and pets. Unused or expired medication should be disposed of properly in accordance with local regulations, preferably through a drug take-back program, to prevent accidental ingestion or environmental contamination.

Disclaimer

This information is intended for educational purposes and does not replace professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting or changing any medication regimen. Individual patient responses may vary, and the safe and effective use of flibanserin requires careful patient selection, adherence to prescribing guidelines, and ongoing monitoring. The prescriber should be familiar with the full prescribing information, including boxed warnings regarding the risks of hypotension, syncope, and CNS depression, especially with alcohol use.

Reviews

Clinical trials and post-marketing surveillance have provided evidence supporting the efficacy and safety profile of flibanserin in the indicated population. In randomized, placebo-controlled studies, premenopausal women with HSDD treated with flibanserin 100 mg daily demonstrated a significant increase in the number of satisfying sexual events and a decrease in distress related to sexual desire compared to placebo. Patient-reported outcomes and validated scales were used to assess efficacy. Adverse events were manageable for most patients with proper dosing and precautions. Long-term data continue to be collected to further characterize the benefit-risk profile in real-world settings. Healthcare providers are encouraged to discuss both the potential benefits and risks with patients to support informed, shared decision-making.