Sildenafil
Erectile Dysfunction Products · Phosphodiesterase type-5 inhibitor
Indications
Treatment of erectile dysfunction.
Dosage
Tab: Adults: 50 mg taken approx 1 hr before sexual activity. Max: 100 mg/day. Max dosing frequency: Once daily. Elderly, impaired hepatic & renal function, initially 25 mg. Children: Not recommended. Susp: Consult prescriber.
Adverse Effects
Headache, flushing, dizziness, abnormal vision, chromatopsia, palpitation, rhinitis, dyspepsia.
Risk Factor (Pregnancy/Lactation)
Contraindications: Men for whom sexual activity is inadvisable (e.g. patients with severe CV disease, established cardiac failure & unstable angina pectoris). Severe hepatic impairment, hypotension (BP <90/50 mmHg), recent history of stroke or MI, known hereditary degenerative retinal disorders e.g. retinitis pigmentosa. Co-administration with nitric oxide donors or organic nitrates in any form. Precautions: A medical history & physical exam should be undertaken to diagnose erectile dysfunction & determine potential underlying causes before Viagra is considered. Increased susceptibility to vasodilators, rare syndrome of multiple system atrophy manifesting as severely impaired autonomic control of BP, resting HTN (BP >170/110), life-threatening arrhythmia within the last 6 month, history of cardiac failure or coronary artery disease causing unstable angina, impaired optic nerve head…
Interactions
Ritonavir, alpha-blockers (e.g. doxazosin), ketoconazole, itraconazole, erythromycin, cimetidine, saquinavir, grapefruit juice, organic nitrates in any form, nitric oxide donors.
Advice to Patient
Take with or without meals. Contact prescriber if acute allergic reactions, chest pain, dizziness, palpitations, urinary tract infection symptoms, difficulty in breathing, skin rash, swelling of genital areas are present, if erection remains for more than 4 hours or if there is severe penile pain. Be cautious while driving at night or in dim environments. Use condom to prevent sexually transmitted diseases. Have periodic follow-up appointments as advised by prescriber.
Pharmacokinetics
Onset of action: Erectile Dysfunction: Approx. 60 mins. Duration of action: Erectile Dysfunction: 2-4 hrs. Decrease Blood Pressure: <8 hrs. Absorption: Rapidly absorbed from the GI tract. Decreased rate of absorption with food. Delayed absorption with high-fat meal. Bioavailability: 25-63%. Metabolism: Hepatic. Half-life elimination: Terminal: Approx. 4 hrs. Time to peak, plasma: 30-120 mins. Excretion: Mainly via faeces (approx. 80%). Urine (approx. 13%).
Brands with this active ingredient
Compiled by Healify Pharmacy from published drug references. How we compile it →
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