Avanafil

(Stendra)

50, 100, and 200 mg tablets

100 mg orally once daily (range, 50-200 mg) as early as approximately 15 min before sexual activity

Concomitant use with potent CYP3A4 inhibitors^a: Do not use

Concomitant use with moderate CYP3A4 inhibitors^b: Do not exceed 50 mg once daily, approximately 30 min before sexual activity

Concomitant use with an α-receptor antagonist; patients should be stable on the α-receptor antagonist first, then start treatment at 50 mg once daily approximately 30 min before sexual activity

Severe hepatic impairment: No data available; avoid use

CrCl < 30 mL/min: No data available; avoid use

Sildenafil

(Viagra)

25, 50, and 100 mg tablets

50 mg orally up to once daily (range, 25-100 mg) 1 h prior to sexual activity (range, 0.5-4 h)

Geriatric males: 25 mg orally 1 h prior to sexual activity up to once daily

CrCl < 30 mL/min: 25 mg orally up to once daily

Hepatic impairment (mild to moderate): 25 mg orally up to once daily

Concomitant use with potent CYP3A4 inhibitors^a: 25 mg orally up to once daily (maximum dosing frequency of every 48 h if used with ritonavir)

Tadalafil

(Cialis)

2.5, 5, 10, and 25 mg tablets

As needed use: 10 mg orally once daily (range, 5-20 mg) 0.5 h up to 36 h prior to sexual activity

Once-daily use:

2.5 mg orally once daily; may increase to 5 mg once daily

CrCl 30-50 mL/min - as needed use: starting dose of 5 mg orally; maximum dose of 10 mg not more than once every 48 h; once daily use: no dosing adjustment necessary

CrCl < 30 mL/min – as needed use: maximum dose of 5 mg not more than once every 72 h; once daily use: not recommended

Hepatic impairment (mild to moderate) – as needed use: not to exceed 10 mg daily; once daily use: not extensively studied in this patient population; use caution

Concomitant use with potent CYP3A4 inhibitors^a – as needed use: maximum dose of 10 mg, not to exceed every 72 h; once daily use: 2.5 mg orally daily

Vardenafil

(Levitra and Staxyn)

Levitra: 2.5, 5, 10, and 25 mg tablets

Staxyn: 10 mg orally disintegrating tablets

Oral tablet: 10 mg orally once daily (range, 5-20 mg) 1 h prior to sexual activity

Orally disintegrating tablet: 10 mg orally once daily 1 h prior to sexual activity; maximum dose of 10 mg daily; if lower dose required, use regular tablet

Geriatric males: initial dose of 5 mg orally once daily

Hepatic impairment (moderate): initial dose of 5 mg orally once daily, not to exceed 10 mg daily; do not use orally disintegrating tablet in patients with moderate or severe hepatic impairment given higher systemic exposure than regular tablet

Concomitant use with an α-receptor antagonist: patients should be stable on the α-receptor antagonist first, then vardenafil may be added; reduce initial dose to 5 mg (or 2.5 mg if certain CYP3A4 inhibitors also given)

Concomitant use with potent CYP3A4 inhibitors^a: 2.5 or 5 mg up to once daily depending on the agent (maximum dosing frequency of every 72 h if used with ritonavir)

Darifenacin (Enablex)

7.5 and 15 mg extended-release tablets

7.5 mg extended-release tablet once daily initially; may increase to 15 mg once daily after 2 weeks if needed

Concomitant use with potent CYP3A4 inhibitors^a: do not exceed 7.5 mg daily

Not recommended for use in patients with severe hepatic impairment; for patients with moderate hepatic impairment, do not exceed 7.5 mg daily

Fesoterodine (Toviaz)

4 and 8 mg extended-release tablets

4 mg extended-release tablet once daily initially; may increase to 8 mg once daily if needed

Concomitant use with potent CYP3A4 inhibitors^a: do not exceed 4 mg daily

Not recommended for use in patients with severe hepatic impairment

For patients with severe renal impairment, do not exceed 4 mg daily

Oxybutynin (Ditropan XL; immediate-release formulations and extended-release 15 mg tablets are available only as generics)

Immediate-release: 5 mg tablets; 5 mg/5 mL solution and syrup

Ditropan XL: 5, 10, and 15 mg extended-release tablets

Immediate-release: 5 mg 2-3 times daily; maximum of 5 mg 4 times daily (20 mg daily)

Extended-release: 5-10 mg once daily; dose may be increased by 5 mg weekly; maximum dose of 30 mg daily

Immediate-release; geriatric patients: 2.5 mg 2-3 times daily initially, 5 mg 3 times daily may be tolerated

Lower dosages of immediate-release may be needed in hepatic impairment; extended-release formulations not recommended for use in hepatic impairment

Extended-release formulations not recommended in severe renal impairment

Solifenacin (Vesicare)

5 and 10 mg tablets

5 mg once daily; may increase to maximum of 10 mg once daily

Concomitant use with CYP3A4 inhibitors: do not exceed 5 mg daily

CrCl ≤ 30 mL/min: do not exceed 5 mg daily

Not recommended for use in patients with severe hepatic impairment; do not exceed 5 mg daily in patients with moderate hepatic impairment

Tolterodine (Detrol and Detrol LA)

1 and 2 mg immediate-release tablets

2 and 4 mg extended-release capsules

Immediate-release: 2 mg twice daily; may reduce to 1 mg twice daily based on response and tolerability

Extended-release: 4 mg once daily; may reduce to 2 mg once daily based on response and tolerability

CrCl ≤ 30 mL/min or hepatic impairment: reduce dose to 1 mg twice daily for immediate-release; 2 mg once daily for extended-release

Concomitant use with CYP3A4 inhibitors: reduce dose to 1 mg twice daily for immediate-release; 2 mg once daily for extended-release

Trospium (both immediate- and extended-release products available as generics only)

20 mg immediate-release tablets

60 mg extended-release capsules

Immediate-release: 20 mg twice daily; may reduce to 20 mg once daily at bedtime based on tolerability; maximum 60 mg daily

Extended-release: 60 mg once daily in the morning

CrCl < 30 mL/min: reduce dose to 20 mg once daily at bedtime for immediate-release; extended-release dosage form not recommended

Use with caution in patients with hepatic impairment

Topical oxybutynin (Gelnique)

10% topical gel

Gelnique 10% topical gel: Apply 1 packet of 10% gel once daily (100 mg)

May be applied to abdomen, upper arms/shoulders, or thighs, rotate site so same site not utilized on consecutive days

No dosing adjustment recommendations

Transdermal oxybutynin (Oxytrol [prescription] and Oxytrol for Women [over-the-counter])^b

3.9 mg/24 h transdermal patch

Apply 1 patch to abdomen, hip, or buttock twice weekly (3.9 mg daily)

Every 3-4 days, rotate site to avoid irritation

Mirabegron (Myrbetriq)

25 and 50 mg extended-release tablets

25 mg once daily; dose may be increased up to 50 mg once daily; maximum dose 50 mg once daily

Moderate hepatic impairment: do not exceed 25 mg once daily; not recommended in severe hepatic impairment

CrCl = 15-29 mL/min: do not exceed 25 mg once daily

CrCl < 15 mL/min: not recommended

Abbreviations: CrCl, creatinine clearance; CYP3A4, cytochrome P450 3A4.

^a Potent CYP3A4 inhibitors include drugs such as erythromycin, ritonavir, ketoconazole, itraconazole, saquinavir
^b Over-the-counter transdermal oxybutynin is approved for women ≥ 18 years; prescription transdermal oxybutynin is approved for women and men