近日，美国食品与药物管理局FDA批准了一种可能起效更快的伟哥和其他勃起功能障碍（ED）治疗药物的替代药物——阿伐那非（Stendra）。
阿伐那非（Stendra）由Vivus公司生产，与伟哥和希爱力属于同一类药品。这些药物均属于5型磷酸二酯酶抑制剂（PDE5-I），通过增加流向阴茎的血流起作用。
FDA声明，患者应在性行为前30分钟服用阿伐那非（Stendra）。但在研究中，该药物已被证明可在短短15分钟内起效，快于其他药物报告的30-60分钟（尽管在研究中没有对它们进行直接比较）。
在临床试验中，77％的ED男性在服用阿伐那非（Stendra）后能够勃起，与之相比服用无效的安慰剂的男性为54％。在患糖尿病相关ED的患者中，63％的男性在服用这种药物后能够勃起，服用安慰剂的男性为42％。Stendra使57％的ED男性能够性交（服用安慰剂的男性为27％），糖尿病相关ED的男性为40％（服用安慰剂的男性为20％）。
阿伐那非（Stendra）与其他PDE5-I相同，不能用于同时服用硝酸盐类治疗胸痛的男性患者，因为其联合使用会导致血压的急剧降低。服用Stendra的男性可能会突然出现单眼或双眼的视力丧失，还有可能突然发生听力丧失或下降。一旦出现上述情况，患者应停止服用，并立即呼叫医生。
在临床试验中发现，阿伐那非（Stendra）的最常见不良反应包括头痛，面部和身体其他部分的潮红，鼻充血，常见的感冒样症状（鼻咽炎）和后背痛。罕见有服用阿伐那非或其他PDE5-I的患者出现阴茎异常勃起可能持续4小时或更长时间。如果这一情况出现，患者应及时就医。

STENDRA Rx
Generic Name and Formulations:
Avanafil 50mg, 100mg, 200mg; tabs.
Company:
Indications for STENDRA:
Erectile dysfunction.

Adult:
Take 1 dose as needed approx. 15 mins before sexual activity at frequency of up to once daily. Initially 100mg. May reduce dose to 50mg taken approx. 30 mins before activity or increase to 200mg taken approx. 15 mins before activity. Concomitant moderate CYP3A4 inhibitors: max 50mg once every 24hrs. Concomitant α-blockers (patients should be stable on α-blocker therapy before starting): initially 50mg.

Children:
<18yrs: not established.

Contraindications:
Concomitant organic nitrates (if medically necessary, allow ≥12hrs to elapse after last avanafil dose before considering initiation). Concomitant guanylate cyclase (GC) stimulators (eg, riociguat).

Warnings/Precautions:
Confirm diagnosis before therapy. Cardiovascular disease (eg, MI, stroke, life-threatening arrhythmia, or coronary revascularization within 6 months; BP<90/50 or >170/100; unstable angina, angina with intercourse, NYHA Class ≥2 CHF, LV outflow obstruction, impaired autonomic regulation of BP): not recommended. Anatomical penile deformation. Predisposition to priapism. Underlying non-arteritic anterior ischemic optic neuropathy risk factors. Advise patients to discontinue if sudden vision or hearing loss occurs. Patients for whom sexual activity is inadvisable or contraindicated. Bleeding disorders. Active peptic ulcer. Severe hepatic or renal impairment, on dialysis: not recommended. Pregnancy (Cat.C).

Interactions:
See Contraindications. Hypotension with nitrates, GC stimulators. Concomitant strong CYP3A4 inhibitors (eg, ketoconazole, ritonavir, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin), CYP450 inducers, or other ED treatments: not recommended. Potentiated by moderate CYP3A4 inhibitors (eg, erythromycin, amprenavir, aprepitant, diltiazem, fluconazole, fosamprenavir, verapamil), grapefruit juice. Additive hypotensive effects with concomitant α-blockers, antihypertensives (eg, amlodipine, enalapril). Increased orthostatic hypotension with substantial alcohol consumption (eg, >3 units); caution. May potentiate nitric oxide donors (eg, sodium nitroprusside), desipramine, omeprazole, rosiglitazone.

Pharmacological Class:
Phosphodiesterase type 5 inhibitor (cGMP-specific).

Adverse Reactions:
Headache, flushing, nasal congestion, nasopharyngitis, back pain; sudden vision or hearing loss; rare: cardiovascular events, prolonged erection, priapism.

How Supplied:
Tabs—30, 100