Creation of the first phosphodeisterase 5 inhibitor (PDE5), sildenafil, in 1988 and then its active application was a great breakthrough in solving the problem of erectile dysfunction. Nowadays, the market of PDE5 inhibitors is represented by four main drugs. High effectiveness and broad application of these drugs does not exclude considerable drawbacks of their usage. Man’s decision itself to consult a specialist and start taking medicinal products takes a deep psycho-traumatizing impact on him. He considers it to be factual confirmation of his damaged sexual function, since from now on, he has to take medications to ensure normal sexual life.
That is why there is a long period of time from ED manifestation to beginning of PDE5 inhibitors usage (taking decision to visit a doctor, searching for a specialist, treatment of not-existing chronic prostatitis, another inadequate therapy, substitution of a doctor due to absence of effect, etc.). Within this time, regardless of ED genesis, sexual neurosis develops, interpersonal relationships with a partner become worse, skepticism towards the problem decision enhances. Thus, the existing concept of PDE5 inhibitors usage “upon demand” divides all men into two groups: healthy ones and the ones suffering from ED. That is why, it is important to go over to a broader application of PDE5 inhibitors. They are indicative to all men experiencing age-related or situational impairment of erection and parallel decrease of sexual activity as opposed to their individual norm. Evident conditions of PDE5 inhibitors administration are patient’s willing and absence of contraindications.
New Conceptual Approach
This approach implies therapeutic effect as opposed to the traditional one that requires episodic correction of ED.
Conceptual approach has two main aspects:
- Modelling (restoration) by episodic intakes of PDE5 inhibitors of the level of copulative activity which was present until ED and depression occurrence.
- Usage of minimally effective doses of PDE5 inhibitors which was possible due to their production in smaller doses (for instance, Levitra 5mg). Prior to that, prescription to each patient was based on individual dose. This was quite inconvenient, since in many cases it led to unreasonable exceeding of dosage.
It is worth mentioning that the approach implying constant course-based intake of PDE5 inhibitors with application of 5mg of tadalafil requires separate discussions.
New Forms of PDE5 Inhibitors
Additional opportunities for the use of PDE5 inhibitors are opening up with the advent of new forms of drugs. Thus, vardenafil (Levitra ODT) has recently been developed and is available for use at Immunepharma, better known as Canadian Pharmacy. It has a tableted shape and gets dispersed right in mouth cavity. This drug became a significant event, since this was the first representative of PDE5 inhibitors group that was more suitable for application than standard pills for swallowing. Previously conducted research studies for the purpose of stating patients’ preferences proved their choice of the given form of the medicine.
It was stated that bioaccessibility of dispersible tablets of vardenafil is 1,3 times bigger than the ones for swallowing. Maximal concentration of vardenafil in blood plasma after one-time intake and onset time of both forms are quite comparable. Significantly, bioaccessibility and maximal concentration of oral dispersible tablets of Levitra were not affected in case of their combination with food. The pills for swallowing had its bioaccessibility decreased when applied with food.
Levitra ODT considerably surpassed the indicators of placebo according to all main and additional indexes. This regularity occurred regardless of patients’ age. The optimal result of ED therapy is restitution of that sexual activity a man had before erectile disorders. During the medical trial, percent share of men who reached normal erection after therapy course was considerably higher with oral dispersible vardenafil than with placebo (40% vs 12%). Most patients reported their satisfaction with Levitra ODT. This vardenafil form was well tolerated by patients. The frequency and character of adverse effect exposed after the intake of 10mg of vardenafil the form of orally dispersed tablet corresponded to safety profile of vardenafil in coated tablets. Side-effects had a mild and moderate degree of manifestation, including headaches (16,4%), blushes (7,5%) and dyspepsia (3,7%).
All in all, application of 10mg of Levitra ODT in the form of orally dispersible tablet “upon requirement” is an effective and well-tolerated method of ED treatment regardless of patient’s age. Being of the same efficiency and safety, orally dispersible tablets of vardenafil are easier to use than coated tablets for swallowing. Thus, vardenafil in the shape of a tablet soluble in mouth cavity is the first similar form of PDE5 inhibitors which is available for practical use. Besides its efficiency, safety, convenience and popularity with patients, it Levitra ODT has other positive characteristics. Appearance of PDE5 inhibitors in the form of orally dispersible tablets change the psychological aspect of therapy with these remedies. The use of a standard form of PDE5 inhibitors makes all sexual episodes to acquire negative connotation due to necessity of taking a medicine reminding a man of his sexual inability. Orally dispersible pills of vardenafil allow avoiding this psycho-traumatizing action.
Under the influence of communication with a physician, administration of tableted vardenafil must be perceived by a man as an element of preparation for sexual intercourse, as a cup of coffee before working day or chocolate before a chess game. It is assumed that patients will give priority to Levitra ODT that allows a number of men to solve the problem of erectile dysfunction once and for all.
Mechanisms of Therapeutic Effect
To treat erectile dysfunction within the framework of the concept of episodic correction, the following mechanisms for realization of therapeutic and curative effect are suggested.
First of all, PDE5 inhibitors administration is used not only for improvement of particular sexual episode, but to normalize copulative activity in a whole preventing all adverse consequences of sexual system deconditioning. Copulative function needs a certain and individual for each man load for maintaining normal morphological and functional condition of its structures. Regardless of ED genesis, accompanying decrease of sexual activity becomes additional factor impairing copulative function. Development of depression occurs on all levels of this complicated and hierarchically organized system. Rare and short-lasting erections determine hypoxia of cavernous tissue with gradual replacement of its smooth-muscled and elastic elements with fibrous structures.
It is evident that each man has his individual optimal level of sexual activity deviation of which leads to impairment of copulative function. For specialist, a pivotal question lies in the determination of optimal level of sexual activity for a certain man. Search for an answer acquired special actuality with appearance of such effective erectogenic medicinal products as PDE5 inhibitors. What criteria should be taken into account for determination of optimal frequency of ejaculations?
The conclusion is to be made based on the following factors and indicators:
- Patient’s age;
- Level of ejaculatory activity which could correspond to man’s demands;
- Manifestation rate of sexual desire and arousal in a whole and before sexual intercourse in particular;
- Mood and general condition in the next hours and days after ejaculation and orgasm;
- Duration of friction stage of copulative cycle.
Second, elements of anxiety and tension accompanying expectation of coitus with ED are removed. On the contrary, confidence in normal performing gives a man possibility to get focused on his feelings and perceive emotional reactions of a partner to get maximal satisfaction with sexual intercourse. Third, normalization of copulative function of a man leads to improvement of inter-personal relationships. Fourth, regular and fully-realized sexual activity takes positive action on cardio-vascular, nervous, endocrine systems, as well as an overall health condition of a man. The experience has shown that well-informed of his condition patient knowing well all advantages of episodic correction of erectile dysfunction can change his attitude towards PDE5 inhibitors usage and acquire positive and optimistic mind set.
