Oral Therapy for Erectile Dysfunction
As defined by the NIH, erectile dysfunction (ED) is the repeated inability to get an erection firm enough for sexual intercourse (NIH consensus conference. Impotence. NIH consensus development panel on impotence.
The International Consultation on Sexual Medicine defined ED as the consistent or recurrent inability to attain and/or maintain penile erection sufficient for sexual performance. These definitions exclude other causes of sexual dysfunction including decreased libido and premature ejaculation. According to most recent studies, 15–30 million men report sexual dysfunction. Impotence has been studied for hundreds of years, but not until the past few decades have we been able to understand and treat so effectively. Even in the early 1900s it was known that vascular, neurologic, and hormonal milieu played a part in erections as physicians performed dorsal vein ligations and testicular transplants. Aphrodisiacs were the oral therapy of the day and included Chinese herbs and other common plant and food items that supposedly affected both desire and potency. However, the complex physiologic, neurologic, and psychological interaction is just starting to be appreciated.
Introduction
Definition
As defined by the NIH, erectile dysfunction (ED) is the repeated inability to get an erection firm enough for sexual intercourse. The International Consultation on Sexual Medicine defined ED as the consistent or recurrent inability to attain and/or maintain penile erection sufficient for sexual performance. These definitions exclude other causes of sexual dysfunction including decreased libido and premature ejaculation. According to most recent studies, 15–30 million men report sexual dysfunction. There has also been an increase in self-reported ED according to the National Ambulatory Medical Care Survey, as men are seeking out simple treatments such as oral phosphodiesterase inhibitors (PDE5) – buy canadian viagra.
Historical Perspective
Impotence has been studied for hundreds of years, but not until the past few decades have we been able to understand and treat so effectively. Even in the early 1900s it was known that vascular, neurologic, and hormonal milieu played a part in erections as physicians performed dorsal vein ligations and testicular transplants. Aphrodisiacs were the oral therapy of the day and included Chinese herbs and other common plant and food items that supposedly affected both desire and potency. However, the complex physiologic, neurologic, and psychological interaction is only just starting to be appreciated.
With the dawn of pharmacologic treatment in the 1980s and advancement in ultrasound techniques, physicians were able to create erections and monitor blood flow into and out of the penis and have a way of measuring efficacy of treatment. Intracavernosal therapy was the primary and most efficacious treatment at that time until the discovery of nitric oxide (NO) and its role in erection physiology. Pharmacological treatment has changed as we understand more about the etiology of ED. It has been eleven years since the FDA approved sildenafil (Viagra®), an oral phosphodiesterase inhibitor, and there is a new algorithm of treatment, which is centered on patients’ goals and motivations and evidencebased principles. Over 70% of ED can now be treated with oral medications. Oral pharmacotherapy is the firstline treatment without question for almost all types of ED according to the AUA/EUA guide lines and the WHOsponsored International Consultation on treatment for ED.
First Line Therapy
With the availability and efficacy of oral medications, primary care physicians are now evaluating and counseling men with ED and beginning treatment. In 2002, the majority of Viagra Australia fast delivery prescriptions were written by primary care physicians (69%) as compared to urologists (13%). With this transition, it is important to be thoughtful in our treatment of ED. First, it is important to know all the different treatment options and not just write a prescription for the patient. Secondly, with more recent evidence, it has been shown that ED may be a precursor to coronary artery disease and is associated with other chronic illnesses such as diabetes mellitus, hyperlipidemia, obesity, hypertension, and depression. When treating ED, it is important to see the patient as a whole and consider medication side effects, interactions, and efficacy in certain populations. As the population ages and men continue to seek out treatment for ED, it is necessary for healthcare providers to be equipped with the proper knowledge about available therapy for ED in order to provide the most appropriate goaldirected therapy.
This chapter will focus on the current first line oral pharmacotherapy for treatment of ED while also looking at the trends toward future oral therapy. Other treatment options will be described in other chapters.