Brand Viagra

Viagra is a drug intended for the treatment of erectile dysfunction. It is prescribed for men aged 18-65. The main component is sildenafil.

Indications

Treatment of erectile dysfunction characterized by an inability to achieve or maintain an erection sufficient for satisfactory intercourse.

Pharmachologic effect

Sildenafil is a potent selective inhibitor of cGMP-specific type 5 phosphodiesterase (PDE5). The physiological mechanism of erection has related to nitric oxide release (NO). It takes place in the cavernous body during sexual stimulation. In turn, it contributes to an increase in cGMP levels, subsequent relaxation of the smooth muscle tissue of the cavernous body and an increase in blood flow.

Sildenafil does not have a direct relaxing effect on an isolated human cavernous body. Otherwise, it enhances the effect of NO by inhibiting PDE5, which is responsible for the breakdown of cGMP.

Mode of application

Brand Viagra is taken orally. Oral dispersible tablets can be taken with or without water. You should wash down the tablet. The tablet should be taken immediately after opening the blister.

The absorption of sildenafil is significantly slowed when used in combination with fatty foods.

For most patients, the recommended dose is 50 mg about 1 hour before sexual intercourse.

The maximum recommended dose is 100 mg. The maximum recommended frequency of use is 1 time/day.

Side effect

  • Immune system: infrequently – hypersensitivity reactions (including skin rash), allergic reactions.
  • Organ of vision: often – blurred vision, impaired vision, cyanopsia; infrequently – pain in the eyes, photophobia, photopsia, chromatopsia, redness of the eyes, changes in brightness of light perception, mydriasis, conjunctivitis, hemorrhage in the eye tissue, cataracts, malfunctioning of the lacrimal apparatus; rarely – swelling of the eyelids and adjacent tissues, a feeling of dryness in the eyes, increased eye fatigue, seeing objects in yellow (xanthopsia), seeing objects in red (erythropsia), conjunctival hyperemia, irritation of the mucous membrane, discomfort in the eyes; the frequency is unknown – non-arteritic anterior ischemic optic neuropathy (NPINS), retinal vein occlusion, visual field defect, diplopia, temporary loss of vision or decreased visual acuity, increased intraocular pressure, retinal edema, retinal vascular disease, vitreous detachment/vitreous traction.
  • Hearing organ: infrequently – a sudden decrease or loss of hearing, tinnitus, earache.
  • Cardiovascular system: often – “hot flashes”; infrequently – tachycardia, palpitations, decreased blood pressure, increased heart rate, unstable angina, AV block, myocardial ischemia, cerebral thrombosis, cardiac arrest, heart failure, ECG abnormalities, cardiomyopathy; rarely – atrial fibrillation, sudden cardiac death, ventricular arrhythmia.
  • Hemopoietic system: infrequently – anemia, leukopenia.
  • Metabolism and nutrition: infrequently – thirst, swelling, gout, uncompensated diabetes, hyperglycemia, peripheral edema, hyperuricemia, hypoglycemia, hypernatremia.
  • Respiratory system: often – nasal congestion; infrequently – nosebleeding, rhinitis, asthma, dyspnea, laryngitis, pharyngitis, sinusitis, bronchitis, increased sputum discharge, increased cough; rarely – a feeling of tightness in the throat, dryness of the mucous membrane of the nasal cavity, swelling of the nasal mucosa.
  • Digestive system: often – nausea, dyspepsia; infrequently – gastroesophageal reflux disease, vomiting, abdominal pain, dry mouth, glossitis, gingivitis, colitis, dysphagia, gastritis, gastroenteritis, esophagitis, stomatitis, abnormal liver function tests, rectal bleeding; rarely – hypoesthesia of the oral mucosa.
  • Musculoskeletal system: often – back pain; infrequently – myalgia, pain in the limbs, arthritis, arthrosis, tendon rupture, tenosynovitis, bone pain, myasthenia gravis, synovitis.
  • Genitourinary system: infrequently – cystitis, nocturia, breast enlargement, urinary incontinence, hematuria, impaired ejaculation, genital edema, anorgasmia, hematospermia, penile tissue damage; rarely – priapism.
  • Central and peripheral nervous system: very often – headache; often dizziness; infrequently – drowsiness, migraine, ataxia, hypertonicity, neuralgia, neuropathy, paresthesia, tremor, vertigo, symptoms of depression, insomnia, unusual dreams, increased reflexes, hypesthesia; rarely – convulsions, repeated convulsions, fainting.
  • Skin and subcutaneous tissues: infrequently – skin rash, urticaria, herpes simplex, itching, increased sweating, ulceration of the skin, contact dermatitis, exfoliative dermatitis; frequency unknown – Stevens-Johnson syndrome, toxic epidermal necrolysis.
  • Other: infrequently – fever, swelling of the face, photosensitivity reactions, shock, asthenia, increased fatigue, the pain of various localization, chills, accidental falls, chest pain, accidental injuries; rarely irritability.

Contraindications

  • Severe liver failure;
  • Severe cardiovascular diseases (severe heart failure, unstable angina, suffered a stroke or myocardial infarction during the last 6 months, life-threatening arrhythmias, arterial hypertension or hypotension;
  • Episodes of non-arteritic anterior ischemic optic neuropathy with loss of vision in one eye;
  • Hereditary retinitis pigmentosa;
  • Use in patients taking continuously or intermittently nitric oxide donors, organic nitrates or nitrites in any form because sildenafil enhances the hypotensive effect of nitrates;
  • Concomitant use of PDE5 inhibitors, including sildenafil, with guanylate cyclase stimulants, can lead to symptomatic hypotension;
  • The simultaneous use of the drug with other agents for the treatment of erectile dysfunction (the safety and effectiveness of combination therapy has not been studied);
  • Simultaneous use of ritonavir;
  • Lactose intolerance, lactase deficiency, glucose-galactose malabsorption;
  • Children and adolescents under 18 years of age;
  • Use in women;
  • Hypersensitivity to sildenafil or to any other drug component.