Cialis, which is in the same class of drugs as Viagra, treats erectile dysfunctional (ED) by improving circulation to the penis, which allows for stronger erections in the presence of sexual stimulation.
Cialis, approved by the Food and Drug Administration in November 2003, was the best-selling erectile dysfunction drug worldwide in 2016, chalking up total sales of nearly $2.5 billion. Its closest competitor, Viagra from Pfizer, had worldwide sales of $1.56 billion in 2016, reflecting the little blue pill’s loss of market exclusivity in most major markets, except the United States.
What sets Cialis apart from Viagra and the other oral ED medications on the market is its availability in two different formulations. Daily Cialis, available in 2.5- and 5-milligram tablets, promises that users who take the drug faithfully every day will be ready whenever the need arises. For those who prefer not to be tied to a daily drug, Cialis is also available in an on-demand formulation.
The latter is available in tablets of 10 and 20 milligrams each that should be taken 30 to 60 minutes before sexual activity. The effects of this form of Cialis last for up to 36 hours, far surpassing the duration of effectiveness of all other ED drugs.
Tadalafil Is the Active Ingredient
Tadalafil, the active ingredient in Cialis, is also prescribed for the treatment of benign prostate hyperplasia, or BPH, a noncancerous enlargement of the prostate gland. Eli Lilly & Company, which holds the patent on Cialis, also markets tadalafil under the brand name Adcirca, a prescription treatment for pulmonary arterial hypertension. PAH is a localized form of high blood pressure that targets the blood vessels that supply the lungs, making breathing difficult and putting an extra strain on the heart.
Tadalafil belongs to a family of drugs known as PDE5 inhibitors, which also includes the active ingredients in Viagra (sildenafil citrate), Levitra and Staxyn (vardenafil hydrochloride), and Stendra (avanafil). These drugs are so called for their unique ability to temporarily disable an enzyme known as phosphodiesterase-5, which can interfere with erectile function, particularly in men with impaired vascular function. The vast majority of ED cases are caused by insufficient blood flow to the penis, which is the form of ED targeted by the PDE5 inhibitors.
Basics of Erectile Function
To better understand how Cialis and the other PDE5 inhibitors work, it’s useful to know the basic mechanisms involved in erectile function. As you are no doubt aware, erection begins in the brain and not in the penis. When the brain is alerted to physical stimuli to the penis or other erogenous zone or feelings of sexual desire, it sends a flood of nitric oxide coursing toward the pelvic region.
On its way toward the pelvic region, the nitric oxide sets off secondary chemical reactions, one of which produces a substance known as cyclic guanosine monophosphate, or cGMP. A key player in erectile function, cGMP then signals the smooth muscle tissue lining the walls of arteries that supply the penis to relax. As these muscles relax, the arteries expand to carry the increased volume of blood needed to facilitate erection.
What Does PDE5 Enzyme Do?
So how does the PDE5 enzyme sabotage erectile dysfunction? One of the enzyme’s primary tasks is to break down cGMP, which poses no particular problem for men with robust vascular function. For them, any cGMP broken down by the PDE5 enzyme will be quickly replaced.
However, for men whose vascular function is already compromised, the PDE5 enzyme often outpaces the body’s ability to replace the cGMP that is broken down. As the levels of cGMP dwindle, so may your erection.
Tadalafil, which has by far the longest half-life of any of the PDE5 inhibitors, can disable the pesky PDE5 enzyme for up to 36 hours. Half-life is the time it takes for a substance, such as a drug, in the body to decrease by half. This example refers specifically to the as-needed formulation of Cialis. The daily version of the drug promises that you’ll be ready for sexual activity whenever the need arises. You just have to remember to take the drug faithfully every day.
Generic Cialis Now Available
Earlier in 2018, Cialis went off-patent in the US. That means that generic formulations of Cialis, sold simply as tadalafil, are now on the market and available by prescription. This is great news for those who want to treat their ED in a more cost-effective manner.
Viagra Also Available in Generic Form
Two generics are also under license for sale in the US, and this has been the case since 2017. They offer some price relief compared to the price of name-brand Viagra. Pfizer’s US patent for Viagra expires in 2020, and at that time, more generics for Viagra are expected to become available, lowering prices further.
To buy Cialis or any of these other ED medications, you will need a prescription. You can get one from your doctor and then purchase Cialis or the ED drug of your choice from a nearby pharmacy. Alternatively, you can order the drug from a reliable online supplier, such as eDrugstore.com, which has been selling FDA-approved drugs online for nearly two decades.
If you have a doctor’s prescription but would prefer to order the drug online, you can fax the prescription or scan and email it along with your order to eDrugstore. If you don’t yet have a prescription and would prefer not to discuss your erection problems with your regular doctor, eDrugstore can set up a complimentary online consultation with one of its team of licensed U.S. physicians. If the doctor determines that you’re an appropriate candidate for the drug, he or she will authorize the prescription. To learn more about erectile dysfunction and the drugs available to treat it, click here to access eDrugstore’s Erection Problems page. And if you are interested in ordering Cialis or its generic equivalent online with outstanding convenience, customer service, and discretion, we invite you to visit eDrugstore.com.
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