Visarsin Ku-tab, 50 mg

A selective inhibitor of cycloguanosine monophosphate (cGMP)-specific FDE5. FDE5, which is responsible for the breakdown of cGMF, is found not only in the corpora cavernosa of the penis but also in the pulmonary vessels.

Indications

According to the instructions, Vizarsin Ku-tab is recommended for use in the treatment of erectile dysfunction, which is characterized by the inability to achieve or maintain penile erection necessary for satisfactory sexual intercourse.

Pharmacological effect

Selective inhibitor of cycloguanosine monophosphate (cGMP)-specific PDE5. PDE5, responsible for the breakdown of cGMP, is found not only in the corpus cavernosum of the penis, but also in the vessels of the lungs.

Special instructions

Before starting drug therapy, in order to diagnose erectile dysfunction and determine the possible causes of their development, it is necessary to study the patient’s medical history and conduct a thorough clinical examination. Since there is a certain risk from the cardiovascular system due to sexual activity, before starting any course of treatment for erectile dysfunction, it is necessary to assess the patient’s condition.

Active ingredient

Sildenafil

Composition

Composition of 1 tablet:

Contraindications

Absolute:

myocardial infarction or cerebrovascular accident (stroke) suffered in the last 6 months;
hypotension (blood pressure below 90/50 mmHg);
severe heart failure, unstable angina and other severe forms of cardiovascular lesions, in the presence of which men are not recommended to have sexual activity;
severe functional disorders of the liver;
congenital fructose intolerance (since sorbitol is included in the composition of Visarsin Ku-tab);
phenylketonuria (because aspartame contained in the product is a source of phenylalanine);
loss of vision in one eye due to non-arteritic anterior ischemic optic neuropathy (non-arteritic AION), regardless of whether this pathology is associated or not with previous use of PDE-5 inhibitors;
hereditary degenerative diseases of the retina (hereditary retinal dystrophies), such as retinitis pigmentosa (with the possible presence of genetic disorders of retinal PDE), since the safety profile of sildenafil in such patients has not been studied;
simultaneous use with NO donors (including amyl nitrite) or nitrates in any form due to the fact that sildenafil can enhance the antihypertensive effect of nitrates (mediated through NO/cGMP);
combined use with other drugs for the treatment of erectile dysfunction, since the effectiveness and safety of Vizarsin Qu-tab in this combination has not been studied;
age under 18 years;
combination with ritonavir;
hypersensitivity to any of the components of the drug.

Visarsin Qu-tab is not intended for use in women.
Relative contraindications (sildenafil should be used with extreme caution in the presence of the following conditions/diseases):

arrhythmias of a life-threatening nature;
multiple system atrophy syndrome or left ventricular outflow tract obstruction [hypertrophic obstructive cardiomyopathy (HOCM), aortic stenosis];
blood pressure readings above 170/100 mm Hg. Art.;
conditions predisposing to the occurrence of priapism (leukemia, multiple myeloma, sickle cell anemia);
anatomical deformation of the penis (cavernous fibrosis, angulation or Peyronie’s disease);
period of exacerbation of gastric or duodenal ulcer, diseases accompanied by bleeding (due to the lack of information on the safety of use);
indications in the anamnesis of episodes of development of non-arteritic AION;
taking alpha-blockers.

Side Effects

nervous system: very often – headache; often – dizziness; infrequently – hypoesthesia, drowsiness; rarely – fainting, cerebrovascular accident; with unknown frequency – convulsions, transient ischemic attack, relapse of convulsions;
gastrointestinal tract: often – dyspepsia; uncommon – nausea, dry mouth, vomiting;
musculoskeletal and connective tissue: infrequently – myalgia;
mammary gland and genital organs: uncommon – bleeding from the penis, hematospermia; with unknown frequency – prolonged erection, priapism;
urinary system: infrequently – hematuria;
skin and subcutaneous tissues: uncommon – skin rash; with unknown frequency – toxic epidermal necrolysis (Lyell’s syndrome), Stevens-Johnson syndrome;
cardiovascular system (CVS): often – feeling of hot flashes; infrequently – tachycardia, palpitations; rarely – atrial fibrillation, increase/decrease in blood pressure, myocardial infarction; with unknown frequency – unstable angina, ventricular arrhythmia, sudden cardiac death;
labyrinthine disorders and the organ of hearing: often – tinnitus, vertigo; rarely – deafness;
organ of vision: often – visual impairment, chromatopsia (impaired color vision); infrequently – impaired lacrimation, damage to the conjunctiva; with unknown frequency – visual field defect, retinal vascular occlusion, non-arteritic AION;
organs of the chest and mediastinum, respiratory system: often – nasal congestion; rarely – nosebleeds;
immune system: rarely – hypersensitivity reactions;
laboratory and instrumental data: infrequently – increased heart rate;
other disorders: infrequently – increased fatigue, chest pain.

Interaction

Possible influence of other drugs/drugs on the pharmacokinetic parameters of sildenafil:

cytochrome P450 isoenzymes (according to in vitro studies): a decrease in clearance may be observed;
inhibitors of the CYP3A4 isoenzyme (including cimetidine, erythromycin, ketoconazole): there is a decrease in drug clearance, but the frequency of adverse reactions does not increase (sildenafil should be started with a dose of 25 mg);
ritonavir (a powerful cytochrome P450 inhibitor), HIV protease inhibitor (2 times/day at a dose of 500 mg): AUC and Cmax in blood plasma increases by 11 and 4 times, respectively, after 24 hours the level of sildenafil in plasma is approximately 200 ng/ml (when taking sildenafil alone – 5 ng/ml; the combination is contraindicated);
saquinavir (CYP3A4 isoenzyme inhibitor), HIV protease inhibitor (3 times/day at a dose of 1200 mg): AUC and Cmax of sildenafil (1 time/day at a dose of 100 mg) increases by 210 and 140%, respectively;
itraconazole and ketoconazole (potent inhibitors of the CYP3A4 isoenzyme): a significant effect on the pharmacokinetics of the drug is possible;
erythromycin (5 days, 2 times/day at a dose of 500 mg): AUC increases by 182%; azithromycin (3 days, 500 mg per day): AUC, Tmax, Cmax, T½ of sildenafil or its main metabolite do not change;
cimetidine (800 mg): plasma concentration of sildenafil (50 mg) increases by 56%;
aluminum/magnesium hydroxide: with a single dose, the bioavailability of the drug does not change;
nicorandil (hybrid of nitrate and potassium channel activator): there is a potential for a serious interaction between these drugs;
thiazides and thiazide-like diuretics, loop and potassium-sparing diuretics, inhibitors of the CYP2C9 isoenzyme (phenytoin, warfarin, tolbutamide), inhibitors of the CYP2D6 isoenzyme (tricyclic antidepressants, selective serotonin reuptake inhibitors), inducers of the CYP450 isoenzyme (barbiturates, rifampicin), antagonists calcium, angiotensin-converting enzyme (ACE) inhibitors, beta-blockers: no changes in the pharmacokinetic parameters of the drug were detected;
grapefruit juice: a slight increase in the level of the active substance in the blood plasma is possible.

Possible effects of Vizarsin Qu-tab on the pharmacokinetics of other medicinal substances/drugs:

cytochrome P450 isoenzymes 2C9, 1A2, 2C19, 2E1, 2D6, and 3A4 [half-maximal inhibition concentration (IC50) ≥150 µmol]: according to in vitro studies, the effect of the drug on the clearance of substrates of these isoenzymes is unlikely;
doxazosin (alpha-blocker) in doses of 4/8 mg: in patients with benign prostatic hyperplasia and stable hemodynamics achieved with doxazosin, rare cases of symptomatic orthostatic hypotension, manifested by dizziness, but without fainting, are possible;
warfarin (40 mg), tolbutamide (250 mg): no interaction with sildenafil (50 mg) was detected;
acetylsalicylic acid (150 mg): additional prolongation of bleeding time when combined with the drug (50 mg) has not been established;
ethanol: when combined with sildenafil (50 mg) in healthy volunteers, the hypotensive effect of ethanol does not increase (Cmax of ethanol in the blood serum is about 80 mg/dl);
alpha-blockers, slow calcium channel blockers, adrenergic neuron blockers, centrally acting drugs, vasodilators, angiotensin II receptor antagonists, ACE inhibitors, beta-blockers, diuretics and other antihypertensive drugs: no differences in side effects with these combinations from the effects in patients taking placebo were noted;
amlodipine: against the background of arterial hypertension, an additional decrease in blood pressure was found, which is comparable to that when using only sildenafil;
saquinavir and ritonavir (HIV protease inhibitors): no changes in the pharmacokinetic parameters of these drugs were noted.

Overdose

With a single dose of Visarsin Qu-tab in doses of less than 800 mg, side effects were similar to those when using sildenafil in lower doses, but the frequency and severity of these disorders increased.

Storage conditions

Store in the original packaging out of the reach of children, at a temperature not exceeding 25 °C.

Shelf life

2 years

Manufacturer

KRKA dd Novo Mesto, Slovenia