希爱力(Tadalafil)的注意事项和药物相互作用

Cialis (Tadalafil) is a phosphodiesterase 5 (PDE5) inhibitor indicated for the treatment of erectile dysfunction (ED), the signs and symptoms of benign prostatic hyperplasia (BPH), and the signs and symptoms of ED and BPH (ED/BPH).

Cialis (Tadalafil) Precautions

1. Patient Assessment

A thorough history and physical examination is recommended to determine the potential underlying cause of erectile dysfunction (ED) and/or benign prostatic hyperplasia (BPH) and to determine an appropriate treatment option.

Before initiating treatment for a patient with BPH, consider the possibility that other urinary tract diseases, including prostate cancer, may be present that may cause similar symptoms.

Patients with large residual urine volumes and/or severely diminished urinary flow should be closely monitored for the presence of obstructive uropathy; these patients may not be candidates for finasteride/tadalafil.

2. Cardiovascular effects

For recent myocardial infarction (within 90 days) or stroke (within 6 months), uncontrolled arrhythmia, hypotension (systolic blood pressure/diastolic blood pressure <90/50mmHg) or uncontrolled hypertension Its safety and effectiveness in treating ED have not been established and its use is not recommended in patients with high blood pressure, heart failure in the past 6 months (New York Heart Association [NYHA] functional class > II), or unstable angina or angina that occurs during sexual intercourse.

Combined use with organic nitrates will enhance the antihypertensive effect and may lead to life-threatening hypotension and/or hemodynamic impairment; simultaneous use is prohibited.

Consider whether patients with underlying cardiovascular disease may be adversely affected by the vasodilatory activity of tadalafil, particularly during sexual activity.

The pictures come from public channels (such as the official website of the FDA, the official website of the original drug manufacturer, etc.) and are for reference only.

3. Simultaneous administration with α-adrenergic blockers

Patients receiving α-adrenergic blockers should be used with caution; due to the additional vasodilation effect, the antihypertensive effect may be enhanced. In some cases, dosage adjustments may be necessary, while in others, concurrent administration is not recommended.

The safety of concurrent therapy may also be affected by insufficient intravascular volume and the use of other antihypertensive drugs.

4. Ocular effects

Post-marketing surveillance experience has rarely reported cases related to non-arteritic anterior ischemic optic neuropathy (NAION), which can lead to vision loss (including permanent vision loss) and is temporally associated with the use of all PDE5 inhibitors. Patients who have experienced NAION in one eye may be at increased potential risk of developing NAION in the other eye.

Not recommended for patients with hereditary degenerative retinal diseases, including retinitis pigmentosa.

5. Ear effects

It has been reported that time-related cases of sudden hearing loss or hearing loss have been reported after the use of all PDE5 inhibitors.

It is unclear whether such effects are directly related to PDE5 inhibitors or whether they are related to other factors.

6. Priapism

May cause prolonged erection (>4 hours) and priapism (painful erection>6 hours).

If priapism is not treated immediately, it can lead to penile tissue damage and permanent loss of function. Use with caution in patients who may be predisposed to priapism (e.g., sickle cell anemia, multiple myeloma, leukemia) or have abnormal penile anatomy (e.g., curvature, cavernous fibrosis, Peyronie's disease).

7. Simultaneous administration with strong CYP3A4 inhibitors or inducers

Consider that tadalafil concentrations may increase or decrease when used concurrently with strong CYP3A4 inhibitors or inducers; in some cases, dosage adjustments may be necessary, while in other cases, coadministration is not recommended.

8. Simultaneous use with other PDE5 inhibitors or ED treatments

The safety and effectiveness of combined use with other PDE5 inhibitors or other ED treatments have not been determined; concurrent use with other PDE5 inhibitors is prohibited.

9. Hematological effects

Tadalafil inhibits PDE5 present in platelets. Although prolonged bleeding times have not been observed in healthy individuals, the manufacturer recommends use with caution in patients with bleeding disorders or active severe peptic ulcers; the risks of treatment should be carefully weighed against the benefits.

10. Potential for drug interactions with once-daily dosing

Once-daily tadalafil monotherapy or finasteride/tadalafil fixed combination therapy will provide sustained tadalafil plasma drug concentrations.

Possible interactions with medications (eg, nitrates, alpha-adrenergic blockers, antihypertensives, and strong CYP3A4 inhibitors) and heavy alcohol consumption need to be considered.

11. Simultaneous use with alcohol

Alcohol and PDE5 inhibitors are both vasodilators; combined use may produce additional antihypertensive effects.

Consumption of large amounts of alcohol (e.g., ≥5 glasses of wine or 5 glasses of whiskey) may cause orthostatic hypotension, which may manifest as increased heart rate, lowered standing blood pressure, dizziness, and headache.

12. Use of fixed combination preparations

When tadalafil and finasteride are used in a fixed combination form, in addition to the general precautions, precautions and contraindications related to tadalafil, finasteride-related content also needs to be considered.

The impact on prostate-specific antigen (PSA) and the use of PSA in prostate cancer detection.

Finasteride causes a decrease (approximately 50%) in serum PSA concentrations within 6 months; even patients with prostate cancer may experience a decrease in PSA.

Establish a new PSA baseline at least 6 months after starting finasteride/tadalafil; monitor PSA regularly thereafter.

Carefully evaluate any confirmed increase in serum PSA concentration during treatment, even if the PSA is within the normal range in men not receiving finasteride.

Noncompliance with treatment may affect PSA concentrations; this should be considered when evaluating test results.

13. Increased risk of high-grade prostate cancer

Finasteride may increase the risk of high-grade prostate cancer.

14. Hypersensitivity reaction

Stevens-Johnson syndrome, exfoliative dermatitis, pruritus, urticaria and angioedema have been reported. It is contraindicated in patients with a history of hypersensitivity reactions to finasteride or tadalafil.

Cialis (Tadalafil) drug interactions

1. Strong CYP3A4 inhibitors

There may be pharmacokinetic interactions (increased Tadalafil exposure). In some cases, manufacturers and experts recommend adjusting tadalafil dosage, setting maximum doses, and/or monitoring safety or effectiveness during combination therapy, while in other cases (i.e., finasteride/tadalafil fixed combination therapy), concurrent use is not recommended.

2. Potent CYP3A inducers

Possible pharmacokinetic interactions (reduced tadalafil exposure) and may lead to reduced efficacy of tadalafil; however, the extent of this reduced effectiveness is unknown. Some experts recommend that when these drugs are taken together, Tadalafil dosage should be titrated based on clinical effect, and coadministration with Cialis (Tadalafil) is not recommended.