Side effects and side effects of sildenafil

In clinical trials, the most common adverse effects of sildenafil include headache, flushing, indigestion, nasal congestion and impaired vision, including photophobia and blurred vision. Some users of sildenafil complained that everything was blue (blue vision). Some people complain about ambiguity and loss of peripheral vision. In July 2005, the FDA found that sildenafil caused visual impairment in rare cases, and many studies have shown the use of sildenafil versus non-arterial ischemic optic neuropathy.

Rare but serious adverse reactions found through post-marketing surveillance include long-term erections, severe hypotension, myocardial infarction (heart attack), ventricular arrhythmias, stroke, elevated intraocular pressure, and sudden hearing loss. In October 2007, the FDA announced that all PDE5 inhibitors (including sildenafil) should require a more pronounced warning of the potential risk of sudden hearing loss.

People who take protease inhibitors to treat HIV infection should be careful. Protease inhibitors inhibit the metabolism of sildenafil, effectively increasing the plasma levels of sildenafil and increasing the incidence and severity of side effects. It is recommended that people who use protease inhibitors limit the dose of sildenafil to no more than 25 mg every 48 hours. Other drugs that interfere with sildenafil metabolism include erythromycin and cimetidine, which also cause an increase in plasma half-life.

The use of sildenafil and an α 1 blocker (typically prescribed for hypertension or for urologic conditions, such as benign prostatic hypertrophy ) at the same time may lead to low blood pressure, but this effect does not occur if they are taken at least 4 hours Apart.

Adverse reactions
1. Cardiovascular system: reports of cardiovascular adverse events such as myocardial infarction, sudden cardiac death, heart failure, arrhythmia, hypotension, cerebral hemorrhage, cerebral thrombosis, transient ischemic shock and hypertension Most of them occur during or just after sexual activity, and occur individually within hours to days after medication or sexual activity, and even a small amount occurs when sexual activity has not taken place shortly after taking the drug. It has not been determined whether these reactions are directly caused by sildenafil or by a combination of factors such as sexual activity and cardiovascular status of patients.
2. Digestive system: dyspepsia (7%), diarrhea (3%); dry mouth, vomiting, difficulty swallowing, glossitis, gingivitis, stomatitis, esophagitis, gastritis, colitis, abnormal liver function, Rectal bleeding and other reports.
3. Blood: A case report of anemia and leukopenia.
4. Metabolism/endocrine system: There are reports of gout, diabetes, peripheral edema, hyperuricemia, hypoglycemia, and hypernatremia.
5. Respiratory system: nasal congestion (4%); asthma, pharyngitis, sinusitis, bronchitis, phlegm, cough, difficulty breathing, etc.
6. Urogenital system: urinary tract infection (3%); cystitis, nocturia, frequent urination, urinary incontinence, abnormal ejaculation, genital edema, lack of orgasm, etc.; also caused prolonged penile erection (more than 4h) Case reports of abnormal erection (painful erection more than 6h) and hematuria.
7. Central nervous system: headache (16%), dizziness (2%); ataxia, hypertonia, tremor, neuralgia, neuropathy, paresthesia, dizziness, depression, anxiety, insomnia, lethargy Case reports such as multiple dreams, slow reflexes, feeling dull, and seizures.
8. Musculoskeletal system: cases of joint disease, muscle pain, tendon rupture, tenosynovitis, bone pain, muscle weakness, synovitis, etc.
9. Skin: Facial flushing (10%), rash (2%), urticaria, herpes simplex, itching, skin ulcers, contact dermatitis, exfoliative dermatitis, etc.
10. Eyes: enlarged pupil, conjunctivitis, ocular bleeding, cataract, dry eyes, eye pain, photophobia, red eye or ocular congestion, burning of the eyes, swelling of the eyes and pressure, increased intraocular pressure, retinal blood vessels Lesions or bleeding, vitreous detachment, edema around the macula, etc. There may also be mild transient visual abnormalities (3%), which are mainly characterized by pale color, enhanced light perception, blurred vision and double vision, transient visual loss or decreased vision.
11. Ear: There are reports of tinnitus and deafness.
12. Others: Systemic reactions such as shock, fatigue, pain (such as chest pain), chills, allergic reactions, etc. may also occur.

Aftereffect
The most common are headache, facial flushing, indigestion and muscle pain, followed by nasal congestion, diarrhea, dizziness and rash. Occasionally, transient visual acuity is usually caused by color discrimination or increased sensitivity to light. The incidence of 100 mg is often higher than the 50 mg dose.

The residual reaction of sildenafil has severe cardiac events (including myocardial infarction, sudden cardiac death, ventricular arrhythmia, cerebrovascular hemorrhage, transient ischemic attack, hypertension), epileptic seizures, anxiety, abnormal erection (pain, erection lasts longer than 6h), hematuria, diplopia, transient loss of vision, decreased vision, oozing blood, eye burning, eye swelling, elevated intraocular pressure, retinal vascular disease or bleeding, vitreous detachment/traction and spots Sexual edema.

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