Cialis - Side Effects & Drug Interactions

Cialis Side Effects:

As like any medicine, there may be some side effects with Cialis (Tadalafil) but not all people who takes Cialis experience side effects. In fact, most people tolerate Cialis well.

The most common side effects are:

Headache
Indigestion
Back pain
Muscle pain
Flushing
Stuffy nose
Pain in arms and legs
Nasal congestion

Patients who get back pain and muscle aches usually get them 12 to 24 hours after taking Cialis and these usually go away by themselves within 48 hours. A small number of patients taking Cialis also reported abnormal vision.

There are some rare side-effects also with Cialis treatment:

Angina
Dry Mouth
Insomnia
Blurred vision
Migraines

It is possible that you may experience some or none of these Cialis side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In previous research studies, up to 3.1 percent of people taking Cialis stopped taking their medicine because of side effects.

Cialis - Drug Interactions

Do not use Cialis if:
• you are allergic to any ingredient in Cialis;
• you have been told by your health care provider not to participate in sexual activity because of certain heart or health problems;
• you are taking or using any type of nitroglycerin (eg, under the tongue, capsule, tablet, spray, patch, ointment, paste) or other nitrates (eg, isosorbide), or recreational drugs ("poppers") containing amyl or butyl nitrate.

Effects of Other Drugs on CIALIS Cytochrome P450 Inhibitors
CIALIS is a substrate of and predominantly metabolized by CYP3A4. Studies have shown that drugs that inhibit CYP3A4 can increase tadalafil exposure.

Ketoconazole —
Ketoconazole (400 mg daily), a selective and potent inhibitor of CYP3A4, increased tadalafil 20-mg single-dose exposure (AUC) by 312% and Cmax by 22%, relative to the values for tadalafil 20 mg alone.

HIV Protease inhibitor —
Ritonavir (200 mg twice daily), an inhibitor of CYP3A4, CYP2C9, CYP2C19, and CYP2D6, increased tadalafil 20-mg single-dose exposure (AUC) by 124% with no change in Cmax, relative to the values for tadalafil 20 mg alone.

Other cytochrome P450 inhibitors —
Although specific interactions have not been studied, other CYP3A4 inhibitors, such as erythromycin, itraconazole, and grapefruit juice, would likely increase tadalafil exposure.

Rifampin —
Rifampin (600 mg daily), a CYP3A4 inducer, reduced tadalafil 10-mg single-dose exposure (AUC) by 88% and Cmax by 46%, relative to the values for tadalafil 10 mg alone.

Drugs Metabolized by Cytochrome P450
CIALIS is not expected to cause clinically significant inhibition or induction of the clearance of drugs metabolized by cytochrome P450 (CYP) isoforms.

Alcohol
Alcohol and PDE5 inhibitors, including tadalafil, are mild systemic vasodilators.

P-glycoprotein (e.g. Digoxin) –
Coadministration of tadalafil (40 mg once per day) for 10 days did not have a significant effect on the steady-state pharmacokinetics of digoxin (0.25 mg/day) in healthy subjects.