What is Cialis?
Known generically as tadalafil, Cialis is a prescription drug indicated for the treatment of erectile dysfunction, benign prostatic hyperplasia (BPH), and BPH with erectile dysfunction. It was approved by the FDA in February of 2003 as a first-line treatment for these disorders, making it the third Phosphodiesterase type 5 (PDE5) inhibitor to be marketed worldwide, next to Pfizer’s Viagra and Bayer’s Levitra. While it is generally well tolerated by most men, commonly reported side effects include headache, indigestion, flushing, and stuffy nose. Self-limiting muscle pain (myalgia), back pain, and abnormal vision have also been reported with Tadalafil use.
How Does it Work?
Cialis works by inhibiting PDE5, an enzyme that specifically degrades cyclic guanosine monophosphate, or cGMP. The process of erection is governed by cGMP activity, which relaxes the smooth muscle cells to increase blood supply to the penile erectile tissues.
During sexual stimulation, the nervous system signals the release of nitric oxide (NO) in the corpora cavernosa—the spongy erectile tissues of the penis. NO stimulates an enzyme (guanylate cyclase) to produce cGMP. However, PDE5 is also prominent in the corpus cavernosa, which binds and gradually breaks down cGMP. By inhibiting PDE5, Cialis prevents the degradation of the chemical messenger cGMP, thereby enhancing erectile responsiveness.
The advantage of Cialis over Other ED drugs
Tadalafil is part of the PDE5 inhibitor group of drugs that are used to treat erectile dysfunction in men. Just like all approved drugs from this group, such as sildenafil and vardenafil, it only works when a man is mentally or sexually aroused. The advantage of Cialis over these other two drugs is its longer half-life (17.5 hours). Simply put, Cialis stays in the body longer, extending its therapeutic effect for up to 36 hours compared with the four- to six-hour duration of Viagra and Levitra. The longer duration of action of Cialis has earned it a fitting nickname “The Weekend Pill.”
This drug is not affected by food consumption, so it may be taken with or without food. It is worth emphasizing that PDE5 drugs require NO to facilitate the conversion of guanosine triphosphate (GTP) into cGMP. Without sexual arousal and nitric oxide production, any PDE5 drug will be ineffective. Please note that Cialis’s longer duration of effect does not come without drawbacks: a longer duration of action is associated with a higher risk for drug interactions.
How to take Cialis
The recommended starting dose of Cialis is 10mg to be taken as needed, at least 30 minutes before anticipated sexual activity. The dose may be decreased to 5mg or increased to 20mg, based on the patient’s tolerability and the drug’s efficacy. Patients should only take one dose per day unless otherwise directed. If patients have benign prostatic hyperplasia or ED with BPH, they might be prescribed with 5mg of Cialis taken once daily. Since the active ingredient of Cialis can remain in the body for more than two days, patients who are suffering from kidney or liver disorders should use caution when taking this medication. If patients are advised to take a daily dose of Cialis, they should take the medication around the same time every day.
How effective is Cialis for Erectile Dysfunction?
In clinical trials, Cialis was able to improve erections by 67% to 81% at 10mg and 20mg doses, respectively, while those in the placebo group reported 35% improvement. Tadalafil also showed success in improving erections in hard to treat subgroups, such as those suffering from diabetes mellitus. According to the European Medicines Agency, a continuous once-a-day regimen with 5mg Tadalafil can act as an alternative to on-demand dosing for couples who anticipate frequent sexual activity.
What to do if Cialis doesn’t work for you?
There are many ways to manage ED. While oral PDE5 is the gold standard in treating general erectile dysfunction in men, it may not always be effective. Cialis may not work because:- Patients are suffering from underlying medical conditions (e.g., diabetes, hypertension, depression, and alcohol misuse, among others) that are poorly managed;
- Patients are taking a dose that is not optimized for their condition;
- Patients need to switch to a different oral agent;
- Or patients have a problem with sexual arousal, which cannot be fixed by PDE5 inhibitors.
In order for ED treatment to succeed, patient education is important. A study found that when 81% of 253 PDE5 inhibitor non-responders were given educational materials and detailed instruction sheets about the drug, more than half of them experienced successful treatment. Treatment education, psychosexual therapy, and improving associated medical conditions all play a role in managing ED successfully.