Dosing and uses of Avanafil (Stendra)
Adult dosage forms and strengths
tablets
- 50mg
- 100mg
- 200mg
Erectile Dysfunction
100 mg PO initially as early as 15 min before sexual activity; not to exceed 1 dose/day
Based on individual efficacy and tolerability, the dose may be increased to 200 mg taken as early as ~15 minutes before sexual activity, or decreased to 50 mg taken ~30 minutes before sexual activity
Use lowest effective dose
Dosage modifications
Coadministration with strong CYP3A4 inhibitors or nitrates: Contraindicated
Coadministration with moderate CYP3A4 inhibitors: Not to exceed dose of 50 mg/24 hr
Coadministration with stable alpha-blocker therapy: Initiate therapy at 50 mg/24 hr
Renal Impairment
- Mild-to-moderate (CrCl ≥30 mL/min): Dose adjustment not necessary
- Severe impairment (CrCl 15-29 mL/min): Safety and efficacy not established; do not use
Hepatic impairment
- Mild to moderate impairment: Dose adjustment not necessary
- Severe impairment: Safety and efficacy not established; do not use
Pediatric dosage forms and strengths
Safety and efficacy not established
Avanafil (Stendra) adverse (side) effects
>2%
Headache (5.6%)
Flushing (3.5%)
Nasal congestion (2.1%)
Nasopharyngitis (3.4%)
Back pain (2.5%)
Upper respiratory infection (<2%)
Bronchitis (<2%)
Influenza (<2%)
Sinusitis (<2%)
Sinus congestion (<2%)
Hypertension (<2%)
Dyspepsia (<2%)
Nausea (<2%)
Constipation (<2%)
Rash (<2%)
<1%
Peripheral edema
Fatigue
Angina
Deep vein thrombosis
Palpitations
Gastritis
Gastroesophageal reflux disease
Hypoglycemia
Hyperglycemia
Oropharyngeal pain
Stomach discomfort
Vomiting
Depression
Insomnia
Cough
Dyspnea exertionaL
Epistaxis
Wheezing
Pruritus
Urinary tract infection
Pollakiuria
Nephrolithiasis
Hematuria
Increased erection
Balanitis
Warnings
Contraindications
Hypersensitivity
Soluble guanylate cyclase (sGC) stimulators (eg, riociguat); concomitant use can cause hypotension
Coadministration with nitrates
- Coadministration with nitrates (either regularly and/or intermittently) and nitric oxide donors
- Consistent with the effects of PDE5 inhibition on the nitric oxide/cyclic guanosine monophosphate pathway, PDE5 inhibitors may potentiate the hypotensive effects of nitrates
- A suitable time interval following PDE5 dosing for the safe administration of nitrates or nitric oxide donors has not been determined
Cautions
Potential for cardiovascular risk during sexual activity in patients with underlying cardiovascular conditions
Monitor patients with left ventricular outflow obstruction (eg, aortic stenosis, idiopathic hypertrophic subaortic stenosis)
Dose should not exceed 50 mg/24hr when taking avanafil concomitantly with moderate CYP3A4 inhibitors
Initiate therapy at 50 mg/24hr if coadministered with antihypertensive medications like alpha-blockers
Priapism may occur especially in patients with predisposed conditions (eg, sickle cell anemia, multiple myeloma, or leukemia)
Discontinue therapy if sudden loss of vision in one or both eyes occur (could be a sign of non-arteritic anterior ischemic optic neuropathy)
Safety and efficacy not established in patients with hereditary retinal disorders, including retinitis pigmentosa (use not recommended)
Sudden hearing loss may occur; discontinue therapy if tinnitus symptoms occur
Alcohol may increase risk for orthostatic hypotension; may increase heart rate and cause dizziness and headache
Pregnancy and lactation
Pregnancy category: C
Lactation: Safety and efficacy not established
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Avanafil (Stendra)
Mechanism of action
Sexual stimulation causes nitric oxide to be released in the corpus cavernosum; nitric oxide activates the enzyme guanylate cyclase, which in turn increases cGMP levels; increase in cGMP levels causes smooth muscle relaxation.
Phosphodiesterase type 5 inhibitors enhance the effects of nitric oxide in smooth muscle relaxation of the corpus cavernosum by inhibiting the degradation of cGMP.
Pharmacokinetics
Half-life elimination: 5 hr
Peak Plasma Time: 30-45 min
Protein Bound: 99%
Metabolism: Liver (via CYP3A4 [major] and CYP2C [minor])
Metabolites: M4 (4% active) and M16 (inactive) are the major circulating metabolites
Excretion: Feces (62%); urine (21%); semen (<0.0002%)
Administration
Instructions
May take with or without food
