Patients with obstruction of blood outflow from the left ventricle (aortic stenosis) may be more sensitive to the action of vasodilators, including inhibitors of PDE. Despite the lack of clinical trials of cases of prolonged erection (longer than 4 hours) and priapism (painful erections lasting more than 6 h), such phenomena are peculiar to this class of drugs. In the event of an erection lasting more than 4 hours (regardless of pain), patients should immediately seek medical help. In the absence of timely treatment of priapism can lead to irreversible damage to the erectile tissue and erectile function.

List of those who must take Zudena with extra caution:

Patients with uncontrolled hypertension, hypotension; 

Patients with hereditary degenerative diseases of the retina (including retinitis pigmentosa, proliferative diabetic retinopathy);
Patients who have undergone over the last 6 months of stroke, myocardial infarction or coronary artery bypass grafting;
Patients with severe hepatic or renal impairment; presence of congenital long QT syndrome, or an increase in the QT interval as a result of taking the drugs; predisposition to priapism; patients with anatomical deformation of the penis; the presence of penile implant; sexual activity in patients with diseases of the cardiovascular system such as unstable angina or angina occurring during sexual intercourse, chronic heart failure (II-IV functional class NYHA classification), which developed during the last 6 months, uncontrolled heart rhythm disorders, - should take into account the potential risk of complications; while receiving of Udenafil and CCBs, alpha-blockers or other hypotensive drugs - may mark the additional reduction in SBP and DBP by 7-8 mmHg.

The drug is not intended for use under the age of 18 years.

Contraindications

Do not use Udenafil in combination with other treatments for erectile dysfunction.

Hypersensitivity to any component of the drug; simultaneous reception of nitrates and other donor of nitric oxide. Do not take Udenafil if you are also using a nitrate drug for chest pain or heart problems. This includes nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate. Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite ("poppers"). Taking Udenafil with a nitrate medicine can cause a sudden and serious decrease in blood pressure.

Effects on ability to drive and operate machinery. Before you manage the equipment and vehicles, patients need to know how they react to the reception of Zudena.

Drug interaction

Consult your doctor before taking Udenafil. Tell your doctor about all your current medicines and any you start or stop using, especially:

- Inhibitors of cytochrome P450 isoenzyme CYP3A4 (ketoconazole, itraconazole, ritonavir, indinavir, cimetidine, erythromycin, grapefruit juice) may enhance the action of Udenafil.

- Ketoconazole (400 mg) increases the bioavailability and Cmax of Udenafil (100 mg) almost 2-fold (212%) and 0.8-fold (85%), respectively.

- Ritonavir and indinavir substantially increases the effects of Udenafil.

- Dexamethasone, rifampin, and anticonvulsants drugs (carbamazepine, phenytoin and phenobarbital) may accelerate the metabolism of Udenafil, so joint application with the above medications weakens the effect of Udenafil.

- The joint application of Udenafil (30 mg / kg orally) and nitroglycerin (2.5 mg / kg once, w / w) did not reveal any effect on the pharmacokinetics of Udenafil in experimental studies, but the simultaneous use of nitroglycerin and of Udenafil is not recommended because of possible reduce blood pressure.

- Udenafil and drugs from the group of alpha-blockers are vasodilator, therefore, in the joint admission should be appointed at the minimum doses.

All medicines may cause side effects, but many people have no, or minor, side effects.

Check with your doctor if any of these most common side effects persist or become bothersome: hives, difficult breathing, your face, lips, tongue, or throat swelling.

Stop using Zudena and get emergency medical help if you have: Palpitations, prolonged erections, flushing, dizziness eye pain, increased lacrimation, nasal congestion, headache.