Cialis Generic (Tadalafil 20mg): Action, How To Take, Precautions

Until recently, Viagra has been the leader on the market of ED (erectile dysfunction) drugs, but surprising discovery of tadalafil has changed the situation dramatically. At the moment, millions of men around the world prefer this medication to traditional slidenafil pills (Viagra and Levitra). Find out what Cialis is, and read about its history.

What is tadalafil?

In order to understand the nature of tadalafil and what it does with male body, it’s crucial to know how the mechanism of erection works. In normal state, smooth muscles and penile tissues are constricted: it prevents blood flow to cavernous body and keeps penis soft. When a man gets sexually aroused, the brain signals body to produce nitric oxide: it promotes faster blood flow. At the same time, nitric oxide triggers release of cyclic guanosine monophosphate (cGMP) – an enzyme that relaxes smooth muscles in penis making them fill up with blood. This process is inhibited by another enzyme, Phosphodiesterase type 5 (PDE5), which prevents blood flow to penile tissues and is used to end the process after sexual intercourse is over. Just like slidenafil, tadalafil suppresses PDE5 enzyme and promotes erection.

History of Cialis

Although Cialis was approved by US Federal Drug Administration for commercial sale in November 2003, its history goes back to 1994. That year, Slidenafil – its analogue used in Viagra and Levitra – was accidentally discovered. Both are phosphodiesterase type 5 (PDE5) enzyme inhibitors and have much the same principle of action.

Curiously, the discovery of the magic drug happened due to accidents. In 1994, scientists from Pfizer medical enterprise were working on a heart drug called “Slidenafil”. Initially, their research implied finding the drug that would help to deal with a row of pulmonary conditions. But during human trials of the medication, the unexpected happened: male volunteers claimed that they experienced unexpected erections after drug intake.

After the trials, Pfizer presented Sildenafil Citrate as a PDE5 inhibiting medication, and later on it was called “Viagra”. The scientists of ICOS Corporation took notes of this drug and worked on their own PDE5 inhibitor: back in 1991, they discovered the compound IC351 with the same abilities together with Glaxo corporation. So when the inhibiting action of this compound was revealed, they started paying closer attention to their own drug. It took them at least two years to finish research and trials.

By 1998, ICOS and Glaxo were no longer cooperating, so the first formed a joint venture with Eli Lilly Company to continue research of IC315. In May 2002, the company finally disclosed to the public that the new PDE5 inhibitor called Tadalafil (that is now produced under brand name Cialis) has lifecycle of 36 hours compared to Slidenafil’s 4-8 hour lifecycle! One year after, Cialis was officially approved for treatment of erectile dysfunction, so now it’s a direct competitor of Pfizer’s Viagra drug.

Curiously, erectile dysfunction is not the only condition that can be treated with Cialis (Tadalafil). In 2011, U.S. Food and Drug Administration also approved it for treatment of Benign Prostatic Hyperplasia and is recommended for men suffering from a combination of symptoms conditioned by BHP and impotence. Since May 2009, there’s a drug called Adcirca – tadalafil medication that is used for treating Pulmonary Arterial Hypertension (PAH). Therefore, the history of multi-purpose medication Tadalafil started with an accidental discovery of Slidenafil, partially related drug.

Mechanism of action

They way Cialis works was mentioned above: it inhibits enzyme PDE5 that makes penile muscles contract and prevents blood flow to tissues. Besides, the medication promotes production of nitric oxide that increases the concentration of cGMP and helps to obtain normal level of enzyme in body. That helps man to achieve solid and durable erection without much effort. Note that tadalafil users don’t usually experience spontaneous erections: they can control the process, and hard-on is achieved after sexual penetration and proper stimulation.

Therefore, Cialis has the following effects:

  1. Promotes easier erections.
  2. Makes erection last longer, while maintenance of hard-on can be perfectly controlled.
  3. Helps to acquire a fully satisfying sexual life.
  4. Treats benign prostate hyperplasia and normalizes male sexual health.

The last effect makes is a good option for men with BPH at initial stages: it prevents further development of disease.

Does Generic Cialis work for everybody?

Unfortunately, Cialis is not equally efficient for everybody. It will only work in men who experience erectile dysfunction because of affected blood flow. If a man has impotence caused by other health conditions, for instance, diabetes, Parkinson’s disease, low level of testosterone, and so on, they should be treated first. Sometimes, total treatment of these diseases helps to restore sexual function normally without using ED medications.

Besides, you should not expect Cialis to boost sex drive, if you have problems with relationships, experience constant stress, or simply don’t find your partner attractive. Therefore, you should solve all issues with your relationships, and, if needed, visit a psychologist. Calm down before sexual intercourse and simply try to enjoy it – you will see considerable changes in your performance.

Sometimes men are not allowed to use Cialis because of cardiovascular problems that can make sexual activity harmful for health, or even life-threatening. But it’s the case when a patient is not fit for sex, not Cialis for the patient. Besides, men with heart strokes, eye problems, possibility of having priapism or deformation of the penis, and certain conditions (myeloma, leukemia, sickle cells anemia) are not recommended to use Cialis, as well.

Of course, people with intolerance to tadalafil in Cialis and other drugs containing it should not use the medication. Although it rarely causes serious complications, allergic reactions may be pretty intense sometimes. The symptoms of allergic reaction include:

  • rash;
  • nasal congestion;
  • watery eyes;
  • problems with breathing;
  • swelling;
  • itching.

Before using Cialis, it’s important to consult with the doctor and take a few tests to make sure that it’s harmless for your body. If Cialis doesn’t work for you for any reason, there are alternative medications.

Why Cialis?

In comparison with Slidenafil contained in Viagra and Levitra, Cialis has much milder and longer effect. A lot of users admit that they love the fact it sustains normal erection within 36 hours, so you can reap its benefits whenever it pleases you. Besides, since the concentration of tadalafil in blood stays at normal level, there’s lower chance of side effects. Therefore, Cialis is a better option for men susceptible to such chemical compounds.

How to take correctly?

There are two different ways you can use Cialis for erectile dysfunction treatment. Traditionally, it can be used by the same principle as Viagra: taken 20-30 minutes prior to sexual intercourse. It will reduce the effect of PDE5 in body quickly, and make cGMP concentration return to the optimal level, but its effect is pretty short. It wears off within 2 days, and PDE5 concentration becomes high again making sex worse.

On the contrary, when you use low-strength Cialis on a daily basis, it helps to maintain optimal level of cGMP in blood constantly enabling you with the opportunity to have fully satisfying sex whenever you want. As a rule, it takes 4-5 days for Cialis to start giving effect, so don’t expect to perform stunningly after the first intake. Some men manage to restore normal sexual activity after a course of Cialis is over, so you should definitely give it a chance.

When taking Cialis, you don’t have to chew it: swallow the entire tablet and drink it up with a glass of water. Good news: tadalafil can be taken with a minor amount of alcohol unlike slidenafil. But if you drink too much, or eat fatty foods, the effect of Cialis can be impaired.


As it has been mentioned, you should inform your doctor about your allergy to tadalafil and similar compounds. Besides, the medication is typically prohibited for people with:

  • heart problems that persisted during the last 6 months (chest pain, heart failure, strokes, etc.);
  • kidney diseases;
  • abnormal blood pressure;
  • severe dehydration;
  • penis conditions, such as scarring, fibrosis, etc.
  • priapism (prolonged erection);
  • leukemia, multiple myeloma, sickle cell anemia;
  • problems with eyes;
  • bleeding disorders;
  • stomach ulcers.

Please note that Cialis can make some users dizzy, so if you drive or operate the machinery, you shouldn’t take the pills: they can affect your performance and alertness.

Side effects

What makes Cialis preferable for many users is lower chance of developing serious side effects. Typically, it causes:

  1. Headache
  2. Stomach upset
  3. Indigestion
  4. Sour stomach
  5. Face flushing
  6. Pain in back

Less common minor side effects may include congestion, burning of throat, eye discharge, muscle stiffness, fever, swelling of joints, voice changes. Major side effects rarely take place, but these can include blurring of vision, chills, sweating, vomiting, loss of hearing or vision. If these happen, you should see a doctor and decide whether Cialis is an appropriate solution.

Now when you know what the history of Cialis is, and how it acts, you can be sure that it’s one of the most efficient products for erectile dysfunction treatment. Although it won’t solve all your problems in relationships, it can definitely help you to restore satisfying, bright sexual life.