How Levitra Affects QT Interval: Canada Pharmacy Cardiologist on Safer Vardenafil Use

Levitra: What Is It?

Levitra is an efficient remedy aimed to struggle against erectile dysfunction and premature ejaculation. The main advantage of the medication lies in its qualitative impact providing a man with strong natural erection. Levitra is composed of only safe ingredients which do not build up addiction even in case of long-term intake. Due to its universalism, this drug is suitable for all age groups. Regular Levitra intake allows getting rid of PE issue, restore hormone production (in particular, testosterone) and increase the duration of sexual intercourse by several times.

Levitra works due to its capacity of enhancing blood circulation. Active components of Levitra take soothing effect not only on penis muscles, but also on blood arteries. Because of this phenomenon, blood stream level to penis increases allowing a man to achieve strong erection. Under the influence of the medication, a patient may experience an enlargement of penis, increase of sexual activity, endurance and muscular tone.

Long-lasting and regular use of the remedy causes amelioration of blood circulation, normalization of hormonal profile, improvement of immunity. Moreover, Levitra has strong anti-inflammatory action which may prevent from inflammatory prosses in penis. Levitra effect starts in 20-30 minutes after the intake and may last up to 36 hours. Medication may be applied in the capacity of therapy course for achieving of maximal effect. But it is worth mentioning that Levitra is not an aphrodisiac. Its action depends on availability of sexual stimulation.

Levitra Components

The principle ingredient of Levitra is vardenafil which is responsible for active blood supply to pelvic organs, enhancement of erection and ejaculation control. In case Levitra is taken in moderate amounts and well tolerated by organism, it may be combined with reasonable dose of alcohol. The effect of substance is aimed at smooth muscle cells of penis. Levitra takes a relaxing effect and increases sensitivity of sexual organ and erogenous zones as well. Levitra auxiliary substances are as follows: lactose, stearate magnesium, sodium, amylum, talc. These ingredients reinforce Levitra’s action. It is issued in the form of capsules with 30mg of active substance.

Indication to Use

Levitra is indicative to men who have difficulties with achievement and preservation of erection. Also, this medication is helpful in treatment of premature emission of seminal fluid, weak libido and overwork. Vardenafil influences physical health of a man, contributes to quality of potency slackened due to sexual disease and weariness. Levitra may be taken for improvement of sexual life quality, prolongation of coitus, increase of penis sensitivity.

Administration and Posology

Levitra is issued in the form of capsules which may be drunk with water. It may be combined with alcohol (maximum 100g of strong alcoholic beverages), vitamins, biologically active supplements and a number of medicinal products. The medication may be taken 20-30 minutes before planned sexual intercourse once a day. Its action lasts within 36 hours. Optimal dosage of vardenafil is 20mg taken once a day. If required, this dosage may be increased.

QT Interval

QT-Interval-2

QT Interval or electric systole of ventricles means the time of beginning of QRT complex till the ending of T wave. QT interval depends on age (children have a less interval size), sex, cardiac rhythm frequency.

Normal QT interval is 0,35-0,44s. QT interval is a constant value for rhythm frequency (for men and women separately). There are special tables which reflect norms of QT for certain sex and rhythm frequency. If electrocardiography result surpasses 0,05 seconds of tabulated value, it demonstrates prolongation of electric systole of ventricles which is a characteristic symptom of cardiosclerosis.

QTcB may allow determining which QT interval of a patient is normal or pathologic (QT interval is considered to be pathologic in case of exceeding of index 0,42).

QT Prolongation Syndrome

One of the most frequent cause of severe cardiac rhythm disorder is QT prolongation syndrome. Either congenital or its acquired forms are connected with the impairment of molecular mechanisms of electrical activity in myocardium cell membranes.

Nowadays QT prolongation syndrome is considered as a group of similar in pathogenesis, clinical presentation, course of disease and conditions prognosis conditions connected with similarity of electrocardiographic manifestations in the form of various degrees of prolongation of QT interval in combination with underlying risk for life-threatening heart beat disorder. It is based on asynchrony of repolarization of various parts of myocardial infarction of the ventricles and increase of its overall duration. Electrocardiographic sign of asynchronous repolarization is prolongation of QT interval as well as the degree of its dispersion. Specific clinical manifestation of this condition is tendency to syncopal conditions of arrhythmic genesis and increased risk for development of fatal cardiac arrhythmias. It is accepted to distinguish congenital and acquired variants of QT syndromes.

Congenital variant represents allelically determined disease which is met in one case among three-five thousand people, moreover 60-70 per cent of patients are women. According to International Registry, in around 85 per cent of cases, a disease is hereditary, whereas around 15 per cent occur due to new spontaneous mutations. Around 10 per cent of patients suffering from prolonged QT interval have observed at least two mutations connected with genesis of this condition which determines variability of its clinical manifestations and inheriting character. This allows suggesting that factual prevalence rate of genotypes is in reality broader than is evaluated based on the number of clinical cases of the given pathology. It is likely that the patients suffering from acquired form of this syndrome are very often latent carriers of such genotypes clinically occurring under the influence of external initiating agents. This supposition makes the application of genotyping justified even in persons with transitory prolongation of QT interval.

Congenital syndrome diagnostics is mainly based on medical case history of a patient in regards to episodes of syncope and pre-syncopal conditions, irregularities of cardiac functioning, arrhythmogenic effect of physical activities and medications taken in recent times. Besides, the presence of all afore-mentioned symptoms and hearing impairments should be ascertained. Analysis of all existing electrocardiograms is a purpose for exposure of changes characteristic for this syndrome and their dynamics.

At the turn of the last century, a system of integral estimation of various diagnostic criteria of long QT syndrome was elaborated. This method remains actual up to now. In order to establish diagnosis, two signs for each group are enough. Differential diagnostics is mainly conducted with the following conditions: transient prolongation of QT interval on the setting of medicinal therapy; ventricular arrhythmia caused by other diseases; idiopathic forms of rhythm disturbance; syncopal conditions of neurogenic origin; Brugada syndrome; epilepsy.

Levitra and QT Interval

QT-Prolongation-Syndrome

A doctor should take due care while prescribing vardenafil to patients with aortal stenosis, obstruction of left ventricle, idiopathic hypertrophic subaortic stenosis, and prolongation of QT interval (including patients with congenital prolongation of QT interval and patients taking medications prolonging QT interval).

During research study of vardenafil influence on congenital and acquired prolongation of QT interval, 59 healthy men took therapeutic doses of vardenafil (10mg) and doses surpassing therapeutic (80mg) and active control – maxifloxacin (400mg) lead to similar increase of QT interval. This observation should be taken into account while prescribing vardenafil. Patients suffering from congenital prolongation of QT interval and patients receiving antiarrhythmics of 1A class (such as quinidine and procaine hydrochloride) and III class (such as amiodarone and sotalol) must avoid taking Levitra.

Thus, in case of Levitra intake in therapeutic (10mg) and supra-therapeutic (80g) dosages, a patient experiences long QT syndrome. Simultaneous intake of vardenafil with other medications taking similar influence on QT interval, lead to summation of effects on prolongation of QT interval in comparison with the intake of each of these medications separately. It should be taken into account in case of Levitra intake by patients with prolongation of QT interval in past medical history or patients who use medications prolonging QT interval. In this regard, Levitra application must be avoided by patients with congenital prolongation of QT interval and by patients taking antiarrhythmics of 1A and III classes.

In case of severe disorders of cardio-vascular system and heart, you have an underlying risk for serious cardiac failures, cerebrum issues or blood vessels during Levitra effect. This may lead to dangerous consequences such as heart or apoplectic attack or sudden death. Moreover, Levitra was connected with rare conditions called the last ischemic optical neuropathy. This problem may cause sudden loss of vision in one or both eyes. In case of vision loss, a patient must seek immediate medical attendance.