Cialis

Cialis (tadalafil) is a medicine used mainly to treat erectile dysfunction (ED) in men. Tadalafil, the active ingredient in Cialis, belongs to a class of drugs known as phosphodiesterase type 5 (PDE-5) inhibitors. These drugs work by relaxing blood vessels in the penis, which improves blood flow and helps to produce and maintain an erection in response to sexual stimulation.

In addition to treating ED, Sialis is also used to treat symptoms of benign prostatic hyperplasia (BPH), such as frequent or urgent urination in men, and may also be used to treat pulmonary arterial hypertension.

Unlike other ED medications such as Viagra (sildenafil), Sialis has a longer duration of action, allowing it to remain effective for up to 36 hours after taking the pill. This gives patients more flexibility in scheduling sexual activity.

Indications Cialis

1. Erectile dysfunction (impotence): Sialis is used to treat erectile dysfunction in men. This condition is characterized by an inability to achieve or maintain an erection of the penis during sexual activity.
2. Benign prostatic hyperplasia: In some cases, tadalafil may be used to treat symptoms of prostate adenoma in men. This includes frequent urination, weak urine flow, feeling of incomplete emptying of the bladder, etc.
3. Simultaneous treatment of erectile dysfunction and prostate adenoma: In some men, erectile dysfunction may be accompanied by symptoms of prostate adenoma. In such cases, Sialis may be effective for treating both conditions.

Release form

Sialis tablets are available in various dosages including 2.5 mg, 5 mg, 10 mg and 20 mg of tadalafil. The choice of dosage depends on the patient's specific needs, degree of ED, and associated medical conditions.

Pharmacodynamics

The pharmacodynamics of Sialis (tadalafil) is due to its ability to inhibit the enzyme phosphodiesterase type 5 (PDE-5), which is found in the smooth muscle cells of blood vessels in the penis, as well as in other parts of the body, including the lungs and bladder muscles.

Mechanism of Action:

• Smooth muscle relaxation: Tadalafil blocks PDE-5, which leads to increased levels of cyclic guanosine monophosphate (cGMP) in smooth muscle. CGMP is an important mediator that helps relax smooth muscle and increase blood flow to the penis, promoting erections in response to sexual arousal.
• Improvement of erectile function: Through this mechanism, Sialis effectively improves erectile function in men suffering from erectile dysfunction by making it easier to achieve and maintain an erection sufficient for sexual intercourse.
• Prolongedaction: One of the features of tadalafil is its prolonged action compared to other FDE-5 inhibitors. Tadalafil can remain active in the body for up to 36 hours, giving patients greater flexibility and spontaneity in sexual activity.

Pharmacokinetics

1. Absorption: Sialis is usually absorbed from the gastrointestinal tract, reaching maximum blood concentrations about 2 hours after administration.
2. Bioavailability: The bioavailability of tadalafil is approximately 80% after oral administration.
3. Distribution: Tadalafil has high affinity to blood plasma proteins and wide volume of distribution. It binds to plasma proteins by 94%.
4. Metabolism: The main metabolism of tadalafil occurs in the liver under the action of cytochrome P450 isoenzyme Zip3A4. Inactive metabolites are formed.
5. Excretion: Tadalafil and its metabolites are excreted mainly with urine (approximately 61%) and with feces (approximately 36%).
6. Half-life: The half-life of tadalafil is approximately 17.5 hours, which ensures its long-lasting effect.

Dosing and administration

1. Dosage: Sialis is available as tablets in various dosage strengths: 2.5 mg, 5 mg, 10 mg, and 20 mg. Usually, the initial recommended dose for most men is 10 mg taken before intended sexual intercourse. However, the doctor may recommend starting with a lower dose (e.g., 5 mg) or increasing to 20 mg depending on the effectiveness and tolerability of the drug.
2. Frequency of use: Sialis is usually taken as needed, 30-60 minutes before sexual activity. The maximum recommended dosing frequency is once a day.
3. Duration of action: The effect of taking Sialis can last up to 36 hours, which allows the patient to be more flexible in scheduling sexual activity. However, this does not mean that the erection will last throughout this time. An erection is only possible in case of sexual arousal.
4. Taking with food: Cialis can be taken independently of meals. However, eating heavy, fatty foods may delay the onset of action of the drug.
5. Individualization of dosage: Dosage and time of administration can be individualized depending on the patient's response to the drug and their needs.

Contraindications

1. Hypersensitivity: People with known hypersensitivity to tadalafil or any other component of the drug should not take it.
2. Nitrates: Sialis interacts with nitrates such as nitroglycerin and it is not recommended to take it at the same time as nitrates. This can lead to a dangerous drop in blood pressure.
3. Heart disease: In people with serious heart disease, such as unstable angina or heart failure, the use of Sialis may be undesirable. You should always consult your doctor before starting to take it.
4. Hypotension: Using Cialis can cause a drop in blood pressure, especially if the person is taking other medicines that can also lower blood pressure. People with hypotension or those taking antihypertensive medications should be careful when using Cialis.
5. Pregnancy and breastfeeding: Sialis is not intended for use in women. There is insufficient data on its safety during pregnancy and breastfeeding.
6. Childhood: Cialis is not intended for use in children and adolescents under 18 years of age.
7. Liver and kidney disease: In people with severe liver or kidney dysfunction, it may be necessary to adjust the dose of Sialis or even stop using it altogether.
8. Contraindications to sexual activity: In people with serious contraindications to sexual activity (e.g. Due to cardiovascular problems), the use of Sialis may be undesirable.

Side effects Cialis

1. Headache: This is one of the most common side effects of using Cialis. The headache may be mild to moderate in intensity and usually goes away on its own.
2. Digestive disorders: These may include diarrhea, nausea, heartburn, or dyspepsia (digestive upset). In most cases, these symptoms may be mild and temporary.
3. Facial redness (facial redness): This can appear as redness or a feeling of heat in the face and neck area. It is usually due to the dilation of blood vessels.
4. Nasal congestion: Some people may experiencenasal congestion or runny nose while using Cialis.
5. Muscle and back pain: This side effect may occur as pain or discomfort in the muscles or back. It usually goes away on its own and does not require special treatment.
6. Visual disturbances: Rarely, temporary changes in vision such as blurred vision, changes in color perception, or increased sensitivity to light may occur. If such symptoms occur, seek medical advice immediately.
7. Hotflashes: Some patients may experience hot flashes (although this is a less common side effect).

Overdose

An overdose of Sialis (tadalafil) may lead to increased side effects such as dizziness, headache, increased heart rate, visual disturbances, nausea and vomiting. In case of overdose, medical attention should be sought. Treatment of overdose may include symptomatic therapy and maintenance of vital body functions.

Interactions with other drugs

1. Nitrates: Interaction with nitrates (e.g. Nitroglycerin) may lead to dangerous decrease in blood pressure. The use of tadalafil in combination with nitrates is contraindicated due to the risk of acute hypotension.
2. Alpha-adrenoblockers: Combination with alpha-adrenoblockers may increase the hypotensive effect and lead to syncope (fainting) in some patients.
3. CYP3A4 inhibitors: Drugs that inhibit the CYP3A4 isoenzyme of cytochrome P450 (e.g. Ketoconazole, erythromycin) may increase the concentration of tadalafil in blood and enhance its pharmacological effects.
4. FDE-5 inhibitors: Combined use with other phosphodiesterase type 5 inhibitors (e.g., sildenafil, vardenafil) may increase the risk of side effects, including hypotension.
5. Antihypertensive drugs: Combined use with other antihypertensive drugs may increase the hypotensive effect and increase the risk of hypotension.