Today, drugs like Cialis have made it possible to treat previously untreatable erectile dysfunctions and are helping millions of people lead a normal and healthy sex life. Erectile dysfunction is the basis of a multi-billion dollar industry. To understand an erectile dysfunction better, it is important to understand how a normal erection occurs. Contrary to popular belief, the brain is the biggest sex organ and all conscious erections are the result of an impulse sent by the brain to the nervous system (the cause of night or sleep erections is still not completely understood). The nervous system then tells the muscular part of the penis the corpus cavernosum to relax.

Once the corpus cavernosum relaxes the membranous cavity around the corpus cavernosum called the tunica albuginea gets filled with blood and the muscular corpus cavernosum then expands. The expansion of the corpus cavernosum is what results in an erection. The draining of blood from the tunica albuginea and the resultant relaxation of the corpus cavernosum results in a loss of erection. One of the leading causes of erectile dysfunction is the lack of proper blood flow to the corpus cavernosum. Erectile dysfunction can thus occur due to low blood pressure, diabetes and rarer conditions like cardio vascular leakage.

Since erectile dysfunction is one of the oldest known sexual problems there is no shortage of folk remedies. What is equally true is that Cialis and Viagra are perhaps the most effective treatments for erectile dysfunction today. Compared to other techniques like surgical implants and pumps, drugs are a simpler and safer means of treating erectile dysfunction. It is important to understand that not all erectile dysfunctions can be treated by drugs, in fact, not all erectile dysfunctions are caused due to physical problems. Mental stress and psychological problems too lead to erectile dysfunction. In addition, excessive drinking is also a known cause of erectile dysfunction and impotence. Contrary to popular belief erectile dysfunction and male impotence were earlier treated as separate entities but today erectile dysfunction and male impotence have become synonyms.

Drugs like Cialis and Viagra use a special mechanism that regulates the release of NO (Nitrous Oxide) in the corpus cavernosum. Without going into too much detail, most drugs that treat erectile dysfunction utilize a phenomenon known as competitive binding, and help improve the duration and quality of the erection. Drugs are therefore not effective in cases where there is physical damage or obstruction.

A popular myth surrounding drugs like Cialis is that drugs alone can induce an erection; it is a proven fact that without adequate mental stimulation an erection is highly improbable. In addition, drugs like Cialis are also being used as aphrodisiacs; once again scientists attribute this to more of a placebo effect. The market today is dominated by 3 major drugs Viagra, Cialis and Levitra, each come with their unique advantages and are usually prescribed based on the particular case and also depending on the prescribing physician's preference. All three work on a similar principle but are chemically different.

It is now possible for people to purchase Cialis online. Since Cialis is not an over the counter drug yet (an experimental over the counter trial with Viagra will be attempted in the UK soon), the only way to purchase Cialis directly from the chemist is via a prescription. Online stores too require a user to fill out a questionnaire. Only once the online questionnaire determines that a person requires Cialis, can a person purchase Cialis online. Already companies like Eli Lilly are working on making improvements to Cialis so that the cases of side effects from Cialis are almost negligible. In fact, all major erectile dysfunctional drugs are under constant development to ensure that there are minimal side effects, and it is only a matter of time before a version of Cialis is developed that is free from any side effects at all.