Common Use

Cialis is an effective, reversible, selective inhibitor of phosphodiesterase type 5 (PDE 5) specific to cyclic guanosine monophosphate (cGMP). It enhances erections by increasing cGMP levels in the penis's cavernous body, promoting blood flow. Cialis has no effect without sexual stimulation and works for 36 hours. The effect can be noticed as early as 16 minutes after taking the medication.

Dosage and Direction

The recommended dose of Cialis is 20 mg, taken at least 16 minutes before sexual activity. The effect lasts for 36 hours. Do not exceed the recommended dose and take it only once daily.

Precautions

Avoid using Cialis with grapefruit juice, alcohol, or tobacco. Smoking while using Cialis may lead to NAION (sudden vision loss). Inform your doctor if you have an abnormal penis, or a history of heart disease, diabetes, liver or kidney failure.

Contraindications

Cialis is contraindicated for patients using any form of organic nitrate, as it may enhance their hypotensive effects.

Possible Side Effects

Common side effects include facial flushing, headaches, stomach upset, diarrhea, and nausea. Rarely, it can cause low blood pressure, blurred vision, and priapism (painful erections lasting over 6 hours). Seek immediate medical help if an erection lasts longer than 4 hours.

Drug Interactions

Avoid taking Cialis with organic nitrates (e.g., Erythrityl Tetranitrate, Nitroglycerin). Drugs like erythromycin and ketoconazole may increase Cialis levels and toxicity. Inform your doctor if you take other medications that may affect Cialis.

Missed Dose

Missed doses do not apply for Cialis as it is taken as needed for erectile dysfunction.

Overdose

Overdose symptoms mirror side effects. Seek medical assistance if you suspect an overdose.

Storage

Store at room temperature, away from moisture, sunlight, children, and pets in a tight container.