Prophylactic Treatment Viagra Online in Canada

Hormonal agents should be cautioned in children due to their ability of promoting fusion of the epiphyseal plate and also the effect on sexual maturation. These agents are contraindicated in children who have not completed sexual maturation and growth or in patients who are attempting to conceive. The use of phosphodiesterase type 5 inhibitors as prophylaxis has been recognized as a result of extensive work into the molecular pathophysiology of priapism, especially in patients with sickle-cell disease. The use of this agent may seem counterintuitive. Early reports suggested the mechanism of phosphodiesterase type 5 inhibitors may be via selective vasodilatation in the corpora. Downregulation of phosphodiesterase type 5 expression has been seen in cavernosal tissue in cases of recurrent priapism. In young adult rats chronically treated with sildenafil, phosphodiesterase type 5 expression is increased.

So the use of phosphodiesterase type 5 inhibitors increases levels of cGMP which leads to increased phosphodiesterase type 5 pro-moter activity and hence transcription and production of the enzyme. This enzyme metabolizes cGMP and controls the excessive cGMP signaling in priapic tissue. Burnett et al. reported on four cases of stuttering priapism, three of who had sickle-cell disease and were treated with phosphodiesterase type 5 inhibitors. The agents were able to reduce the episodes of stuttering priapism and preserve potency. The drug should ideally be taken in the morning to avoid high concentrations at night during sleep related erections. Only one episode of major priapism has occurred with use and this was taken in the evening preceding sexual stimulation.

Phosphodiesterase type 5 inhibitors are generally well tolerated, but may cause headache, facial flushing, rhinitis, and dyspepsia. There may be transient effects on the blood pressure and heart rate as these drugs are vasodilators. They are contraindicated with the use of nitrates.

Adrenergic agents may be administered as self intracorporeal injections in patients who fail or refuse systemic oral therapy for stuttering priapism. McDonald et al. documented success with home self injections of metaraminol in a patient with sickle-cell trait with stuttering priapism. These patients should be taught about the injection site, dosing and systemic adverse effects. It must be emphasized that this is not true prophylaxis, as episodes of priapism are being treated rather than prevented. In addition, there is the potential for adverse systemic effects if drugs Australia Pharmacy shop are injected inadvertently systemically. Alpha agonists are contraindicated in patients with uncontrolled hypertension, coronary insufficiency, and arrhythmia. There have also been case reports of success with use of intracorporeal injections of epinephrine and etilefrine.

Nevertheless, this form of treatment is not preferred over oral systemic prophylaxis.