Levitra
Levitra: instructions for use and reviews
- 1. Release form and composition
- 2. Pharmacological properties
- 3. Indications for use
- 4. Contraindications
- 5. Method of application and dosage
- 6. Side effects
- 7. Overdose
- 8. Special instructions
- 9. Drug interactions
- 10. Analogs
- 11. Terms and conditions of storage
- 12. Terms of dispensing from pharmacies
- 13. Reviews
- 14. Price in pharmacies
Latin name: Levitra
ATX code: G04BE09
Active ingredient: vardenafil (vardenafil)
Producer: Bayer Schering Pharma AG, Germany
Description and photo update: 2019-13-08
Prices in pharmacies: from 941 rubles.
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Levitra is a drug for restoring erectile function, PDE5 inhibitor.
Release form and composition
Levitra dosage form - film-coated tablets: round, biconvex, with a slightly rough surface, from gray-orange to light orange, engraved on one side "5", "10" or "20", on the other - branded Bayer cross (1 or 4 pcs. in a blister, in a cardboard box 1 blister).
The active ingredient of Levitra is vardenafil hydrochloride trihydrate, in 1 tablet:
- 5.926 mg, which is equivalent to 5 mg vardenafil;
- 11.852 mg, which is equivalent to 10 mg vardenafil;
- 23.705 mg, which is equivalent to 20 mg vardenafil.
Auxiliary components: magnesium stearate, crospovidone, anhydrous colloidal silicon dioxide, microcrystalline cellulose.
Additionally, the shell contains: hypromellose, macrogol 400, titanium dioxide, iron oxide red, iron oxide yellow.
Pharmacological properties
Pharmacodynamics
Penile erection is a hemodynamic process during which the smooth muscles of the cavernous bodies and the arterioles located in it relax.
Sexual stimulation leads to the release of nitric oxide (NO) from the nerve endings of the cavernous bodies, which activates the enzyme guanylate cyclase. This leads to an increase in the concentration in the cavernous bodies of cGMP - cyclic guanosine monophosphate. As a result, the smooth muscles of the corpus cavernosum relax, which provides an increase in blood flow to the penis. The cGMP content is regulated both by the synthesis of guanylate cyclase and by the cleavage of cGMP by hydrolysis by phosphodiesterases (PDEs). The most famous PDE is phosphodiesterase type 5 (PDE5), which has specific properties for cGMP.
Vardenafil blocks PDE5, which is responsible for the cleavage of cGMP, thereby intensifying the local action of endogenous nitric oxide in the corpora cavernosa during sexual stimulation. The increase in cGMP levels caused by inhibition of PDE5 causes relaxation of the smooth muscles of the corpus cavernosum and an increase in blood flow to them. Thus, Levitra is able to enhance the natural response to sexual stimulation.
Vardenafil is a potent PDE5 inhibitor with a high level of selectivity (inhibitory concentration in relation to PDE5 averages 0.7 nM). The substance exhibits inhibitory properties with respect to PDE5 to a greater extent than to other known PDEs (1000 times more than to PDE-2, 3, 4, 7, 8, 9, 10, 300 times more than to PDE11, 130 times more than for PDE1 and 15 times more than for PDE6).
Taking Levitra at a dose of 20 mg is able to induce an erection state (sufficient to ensure penetration) within 15 minutes. The reaction to the drug is most fully manifested after 25 minutes.
Pharmacokinetics
After oral administration, vardenafil is absorbed at a high rate. When taken before meals, the first peak of the maximum concentration of the substance is sometimes reached after 15 minutes, but in 90% of patients the maximum level is recorded on average after 60 minutes (range is from 30 to 120 minutes).
The effect of the "first pass" through the liver is significant, so the absolute bioavailability is approximately 15%. When using the drug in therapeutic doses (5–20 mg), the area under the concentration-time curve (AUC) and the maximum concentration increase in proportion to the dose taken.
With the simultaneous administration of vardenafil with food, which contains a large amount of fat (57% and higher), the absorption rate decreases, and the maximum level of the substance in the blood is reached after at least 60 minutes. In this case, the maximum concentration itself decreases on average by about 20% without significant variation in the AUC indicator. When taken with normal food containing no more than 30% fat, the pharmacokinetic parameters of vardenafil (maximum concentration and time to reach it, AUC) do not change. From this it follows that Levitra can be prescribed regardless of food intake.
On average, the volume of distribution of vardenafil at a stable state of pharmacokinetic parameters is 208 liters, which indicates a good distribution of the substance in the tissues. Vardenafil and its main metabolite (M1) bind to a large extent with blood plasma proteins (about 95%), and this property belongs to the category of reversible and is not determined by the total concentration of the drug.
90 minutes after taking Levitra, no more than 0.00012% of the taken vardenafil dose is determined in the semen of healthy patients.
Vardenafil is metabolized mainly by hepatic enzymes with the participation of the cytochrome CYP3A4 system, as well as CYP2C9 and CYP3A5 isoforms. On average, the half-life of the active component of Levitra is 4-5 hours, and the main metabolite M1, which is formed during the desethylation of the piperazine part of the molecule, is about 4 hours. In the blood, glucuronide is determined in the form of a conjugate (glucuronic acid), which is part of the M1 metabolite. The content of the rest (non-glucuronic) part of the M1 metabolite reaches 26% of the total vardenafil content. The selectivity profile for phosphodiesterase in vardenafil is similar to that of M1. The metabolite's ability to inhibit PDE5 in vitro is 28% compared to the active component of Levitra, which corresponds to 7% of the drug's effectiveness.
The total clearance of vardenafil is 56 l / h, and the final half-life reaches 4-5 hours. After oral administration, the substance in the form of metabolites is excreted mainly through the gastrointestinal tract (91–95%), to a lesser extent through the kidneys (2–6% of the administered dose).
In healthy elderly men (over 65 years old) compared with younger patients (up to 45 years old), the hepatic clearance of vardenafil decreases. On average, in elderly patients treated with Levitra, AUC increases by 52%. However, in young and old patients, no differences in the safety and efficacy of the drug were recorded.
In patients with mild renal dysfunction (CC more than 50–80 ml / min) and moderate (CC more than 30–50 ml / min) severity, the pharmacokinetic parameters of vardenafil are practically similar to those in healthy men. In severe renal dysfunction (CC less than 30 ml / min), the average AUC increases by 21%, and the maximum concentration of vardenafil in the blood decreases by 23%. There were no signs of a significant relationship between the content of the active component of Levitra in plasma and creatinine clearance. In patients undergoing hemodialysis, the pharmacokinetics of vardenafil is not well understood.
In patients with mild to moderate liver dysfunctions, vardenafil clearance decreases in direct proportion to the degree of liver dysfunction. With mild liver failure (class A according to the Child-Pugh scale), there is an increase in AUC and maximum concentration by 1.2 times (AUC - by 17%, maximum concentration - by 22%), and with a moderate degree (stage B according to the Child - Pugh scale) - 2.6 (160%) and 2.3 (130%) times, respectively. In patients with severe liver dysfunctions (class C according to the Child-Pugh scale), the pharmacokinetics of vardenafil has not been adequately studied.
Indications for use
According to the instructions, Levitra is used for erectile dysfunction, a man's inability to achieve and maintain an erection required for intercourse.
Contraindications
- Combination with indinavir, ritonavir and other HIV protease inhibitors;
- Simultaneous intake of nitric oxide or nitrate donors;
- Age under 16;
- Hypersensitivity to drug components.
Levitra is not intended for use in women.
It is recommended to use with caution in patients with anatomically deformed penis (Peyronie's disease, cavernous fibrosis, curvature), congenital lengthening of the QT interval, pathologies predisposing to priapism (multiple myeloma, sickle cell anemia, leukemia), severe liver dysfunction, end-stage renal disease, arterial hypotension (systolic pressure at rest less than 90 mm Hg), recent myocardial infarction or stroke, unstable angina pectoris, degenerative hereditary diseases of the retina (including retinitis pigmentosa), exacerbation of peptic ulcer disease, a tendency to bleeding, idiopathic hypertrophic or subaortic stenosis.
Instructions for use of Levitra: method and dosage
Levitra tablets are taken orally with or without food.
Adequate efficacy of the drug is achieved with a sufficient level of sexual stimulation.
Recommended dosage: 10 mg once a day, no more than 5 hours before sexual activity, usually 0.5-1 hour before intercourse. The dose can be reduced to 5 mg or increased, but not more than 20 mg, depending on the individual tolerance and effectiveness of the drug.
The dosage regimen does not need correction in case of moderate or mild renal dysfunction, drug intake by elderly patients, minor liver failure.
Patients with moderate hepatic impairment should start taking Levitra tablets at a dose of 5 mg per day, then gradually increase the dose to 10 and 20 mg, taking into account the effectiveness and tolerability of the drug.
Side effects
The likelihood of possible side effects: ≥10% - often, ≥1% - rarely, ≥0.1% - <1% - sometimes:
- Cardiovascular system: often - hot flashes (feeling of heat, sudden periodic redness of the face); sometimes - increased blood pressure (BP), orthostatic hypotension, decreased blood pressure, myocardial ischemia, angina pectoris;
- Nervous system: often - headache; rarely - dizziness; sometimes - anxiety, drowsiness, fainting;
- Digestive system: sometimes - nausea, dyspepsia, impaired liver function tests (increased alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGTP));
- Reproductive system: sometimes - painful erection, lengthening of erection, priapism;
- Respiratory system: sometimes - shortness of breath, congestive hyperemia of the nasal mucosa (rhinitis, mucosal edema, rhinorrhea), epistaxis, laryngeal edema;
- Musculoskeletal system: sometimes - back pain, myalgia, increased creatine phosphokinase (CPK), increased muscle tone;
- Organ of vision: sometimes - a violation of the brightness of vision, increased tearing, an increase in intraocular pressure;
- Dermatological reactions: sometimes - facial edema, photosensitivity;
- Others: sometimes - hypersensitivity reactions.
In addition, post-marketing studies have reported rare cases of visual impairment due to anterior ischemic neuropathy of the optic nerve, up to persistent vision loss. Most often, these conditions occur when patients have concomitant risk factors, such as smoking, age over 50 years, anatomical defect of the optic nerve head, diabetes mellitus, coronary heart disease, arterial hypertension, hyperlipidemia. The connection between the development of anterior ischemic neuropathy of the optic nerve and the administration of Levitra has not been finally established.
Overdose
Studies carried out in patients who were prescribed Levitra in dosages of 40 mg 1 time per day and 80 mg 1 time per day for 4 weeks showed the absence of significant adverse reactions during treatment. However, when using the drug in a dosage regimen of 40 mg 2 times a day, patients have severe pain in the lumbar spine, which is not accompanied by a toxic effect on the nervous and muscular systems.
Supportive and symptomatic therapy is prescribed as treatment. Since vardenafil is largely associated with plasma proteins and only a small amount of the substance is excreted through the kidneys, the effectiveness of hemodialysis is insignificant.
special instructions
The appointment of Levitra should be made by a doctor after assessing the state of the patient's cardiovascular system, since the risk of heart complications increases during sexual activity.
Levitra should not be prescribed to men with concomitant pathologies of the cardiovascular system, in which sexual activity is contraindicated.
The use of vardenafil has a vasodilating effect and can cause a slight or moderate decrease in blood pressure.
With obstruction of the left ventricular outflow tract (including aortic stenosis, idiopathic hypertrophic subaortic stenosis), the patient may be sensitive to the action of a PDE5 inhibitor.
Patients with congenital prolongation of the QT interval or while taking quinidine, procainamide, amiodarone, sotalol and other class IA and class III antiarrhythmic drugs should not be prescribed the drug, since taking even 10 mg of the drug causes an extension of the QT interval.
Due to the lack of information about the consequences of therapy, Levitra is not recommended for use in severe liver dysfunction, end-stage renal disease (requiring hemodialysis), arterial hypotension, myocardial infarction or stroke in the last 6 months, unstable angina pectoris, hereditary degenerative retinal pathology (pigmented retinitis).
In case of sudden loss of vision, you should stop taking Levitra and urgently seek the advice of your doctor.
The combination with alpha-blockers can lead to the development of arterial hypotension, since both drugs have a vasodilating effect. This combination is permissible only with a stable blood pressure against the background of the use of alpha-blockers and taking Levitra at a dose of no more than 5 mg.
Taking vardenafil may coincide with the use of tamsulosin, other alpha-blockers should not be taken concurrently with the drug.
When taking Levitra in a selected dose, treatment with alpha-blockers should be started with a minimum dose. A gradual increase in the dose of alpha-blockers during therapy with PDE5 inhibitors can cause a further decrease in blood pressure.
If necessary, the simultaneous administration of itraconazole, ketoconazole, erythromycin, the dose of vardenafil should not exceed 5 mg, itraconazole and ketoconazole - 200 mg.
In case of a tendency to bleeding and exacerbation of peptic ulcer disease, it is recommended to use the drug after assessing the ratio of the expected benefit and potential risk of therapy.
Levitra has no effect on the duration of bleeding both in monotherapy and in combination with acetylsalicylic acid.
The drug does not increase platelet aggregation that has developed while taking other drugs.
Exceeding the therapeutic dose of vardenafil leads to a slight increase in the antiplatelet effect of sodium nitroprusside, which is a nitric oxide donor.
For patients whose activities are related to the direct control of vehicles and mechanisms, before using Levitra, it is necessary to establish the degree of individual reaction to the action of the drug.
Influence on the ability to drive vehicles and complex mechanisms
Before starting to drive vehicles or work with moving mechanisms, patients should find out the individual reaction of their body to taking Levitra.
Drug interactions
The hepatic enzymes of the cytochrome P 450 system (isoenzymes CYP3A4, CYP3A5, CYP2C) are involved in the metabolism of vardenafil, inhibitors of which, to a greater or lesser extent, can reduce the clearance of vardenafil. Therefore, when combined with powerful inhibitors of CYP3A4 (itraconazole, ketoconazole, indinavir, ritonavir), a significant increase in the concentration of vardenafil in blood plasma is possible.
With the simultaneous use of Levitra:
- Cimetidine (a nonspecific inhibitor of isoenzymes of the cytochrome P 450 system) at a dose of 400 mg 2 times a day does not affect the maximum blood concentration (C max) and AUC of vardenafil (20 mg);
- Erythromycin (500 mg 3 times a day) 4 times increases the AUC of vardenafil taken at a dose of 5 mg and increases the C max of vardenafil 3 times;
- Ketoconazole (200 mg) causes an increase in AUC of vardenafil (at a dose of 5 mg) by 10 times and C max of vardenafil by 4 times;
- Indinavir (HIV protease inhibitor) at a dose of 800 mg 3 times a day increases the AUC of vardenafil (10 mg) by 16 times and the C max of vardenafil by 7 times (the concentration of vardenafil in plasma 24 hours after administration decreases to 4% of its C max);
- Ritonavir in a therapeutic dose of 600 mg 2 times a day lengthens T 1/2 of vardenafil (5 mg) to 25.7 hours, increases C max of vardenafil 13 times and its total daily AUC 49 times;
- Nitroglycerin at a dose of 0.4 mg, taken sublingually within 24-1 hours after taking Levitra (10 mg), does not enhance its hypotensive effect;
- Maalox (antacid, magnesium hydroxide or aluminum hydroxide) does not affect the AUC and C max of vardenafil;
- Ranitidine (300 mg per day) and cimetidine (800 mg per day) do not affect the bioavailability of the drug.
The combination of 20 mg vardenafil and 3.5 mg glyburide has no mutual effect on the AUC and C max.
There was no pharmacodynamic or pharmacokinetic interaction with the combination of 20 mg vardenafil and 25 mg warfarin.
Simultaneous administration of 20 mg Levitra and 60 or 30 mg of nifedipine does not cause significant pharmacokinetic interaction.
The hypotensive effect of ethanol taken at a dose of 500 mg per 1 kg of patient weight does not increase with the use of 20 mg of vardenafil.
There is no drug interaction when Levitra is combined with digoxin.
The pharmacokinetics of vardenafil are not influenced by angiotensin-converting enzyme inhibitors, acetylsalicylic acid, beta-blockers, hypoglycemic drugs (sulfonylurea, metformin), diuretics, weak CYP3A4 inhibitors.
Analogs
Levitra analogues are: Levitra ODT, Adamax, Viagra, Jenagra.
Terms and conditions of storage
Store in a dry place, out of reach of children, at temperatures up to 30 ° C.
The shelf life is 3 years.
Terms of dispensing from pharmacies
Dispensed by prescription.
Reviews about Levitra
According to reviews, Levitra has established itself as an effective drug for the treatment of erectile dysfunction. Patients respond positively to the drug and praise it, noting the possibility of taking the drug together with alcoholic beverages and using it by men aged 18 to 75 years, as well as by those who suffer from cardiovascular diseases.
Doctors consider Levitra to be an intense potency regulator capable of enhancing the natural response to sexual stimulation to the extent that it allows a full-fledged intercourse with penetration.
The price of Levitra in pharmacies
The approximate price for Levitra with a dosage of 5 mg is 935-1064 rubles (per 1 tablet). You can buy the drug with a dosage of 10 mg for 1477–1507 rubles (for 2 tablets) or 2788–2798 rubles (for 4 tablets). Levitra in a dosage of 20 mg is available at a price of 1013–1154 rubles (for 1 tablet) or 3257–3521 rubles (for 4 tablets).
Levitra: prices in online pharmacies
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Drug name Price Pharmacy |
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Levitra 20 mg film-coated tablets 1 pc. 941 RUB Buy |
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Levitra 20 mg film-coated tablets 4 pcs. 3561 RUB Buy |
Anna Kozlova Medical journalist About the author
Education: Rostov State Medical University, specialty "General Medicine".
Information about the drug is generalized, provided for informational purposes only and does not replace the official instructions. Self-medication is hazardous to health!
