Silodosin Use in Females
Silodosin is not indicated for use in females and should not be prescribed to women. 1
FDA Labeling and Regulatory Status
The FDA drug label explicitly states that silodosin is not indicated for use in females. 1 This is a definitive contraindication based on:
- Pregnancy Risk: The label clearly states "Silodosin is not indicated for use in females" under the pregnancy risk summary section 1
- Lactation: Similarly, under lactation considerations, the label reiterates "Silodosin is not indicated for use in females" 1
- No female study data: All clinical development programs exclusively enrolled male patients 1
Clinical Evidence Base
The entire evidence base for silodosin consists exclusively of studies in men with benign prostatic hyperplasia (BPH):
- European Association of Urology guidelines (2023) reference silodosin only in the context of male lower urinary tract symptoms associated with BPH 2
- All phase 3 trials enrolled only male patients with BPH, with over 800 men studied at the 8 mg daily dose 3
- Safety data from 1,581 patients exposed to chronic silodosin treatment were all male 3
- Cochrane systematic review (2017) included 19 studies with 4,295 randomized participants—all were men with BPH 4
Mechanism and Rationale for Male-Only Use
Silodosin is a highly selective alpha-1A adrenergic receptor antagonist designed specifically to target prostatic smooth muscle:
- Target organ specificity: The drug works by antagonizing alpha-1A receptors in the prostate and urethra to cause smooth muscle relaxation 5, 6
- Disease-specific indication: It is approved exclusively for treating lower urinary tract symptoms associated with benign prostatic hyperplasia—a male-only condition 6
- No female urological indication: Women do not have a prostate gland, which is the primary therapeutic target 5
Important Clinical Considerations
Why This Matters
While alpha-blockers as a drug class have been studied off-label for female urological conditions in some research contexts, silodosin specifically:
- Has zero safety or efficacy data in women 1
- Has no established dosing for females 1
- Carries unknown risks in pregnancy and lactation beyond the general statement of non-indication 1
Common Pitfall to Avoid
Do not extrapolate data from other alpha-blockers (such as tamsulosin or alfuzosin) that may have limited off-label use in women for conditions like ureteral stones. Silodosin has a different selectivity profile (583-fold greater affinity for alpha-1A versus alpha-1B receptors) and has never been studied in females. 6
Bottom line: Silodosin should never be prescribed to female patients. There is no approved indication, no safety data, and no clinical rationale for its use in women. 1