Cialis and Finasteride Interaction: What You Should Know

Cialis contains Tadalafil, which treats Erectile Dysfunction (ED) and Benign Prostatic Hyperplasia (BPH), a condition characterized by an enlarged prostate. Finasteride also treats BPH, but it works differently by lowering Dihydrotestosterone (DHT), gradually reducing prostate size. It is also used for male pattern hair loss.

Because Cialis and Finasteride both help manage BPH, doctors may prescribe them together in some men. This naturally raises concerns about whether taking the two medications together can cause an interaction. The good news is that no major interaction between these medicines has been reported.

In fact, their combination is also FDA-approved as a fixed-dose combination, Entadfi. It contains 5 mg of both active ingredients in a single capsule to manage BPH-related urinary symptoms.

This article explains the Cialis and Finasteride interaction and the side effects associated with each medication. You’ll also learn about tips for taking them safely together and who should avoid this combination.

Is there any interaction between Cialis and Finasteride?

No, Cialis (Tadalafil) and Finasteride don’t have a known direct interaction and can be taken together when prescribed for BPH. They work through different mechanisms and provide complementary effects. Finasteride is a 5-alpha-reductase inhibitor that lowers DHT levels, gradually reducing prostate size.

This can improve urine flow and BPH symptoms, although noticeable benefits may take several months to appear. In contrast, Cialis is a Phosphodiesterase Type 5 (PDE5) inhibitor that promotes smooth muscle relaxation and helps improve BPH urinary symptoms. It also increases penile blood flow during sexual stimulation, helping men who have ED along with BPH.

Because Cialis can provide earlier symptom relief, using them together may offer better control of BPH symptoms. Clinical studies have supported this claim, showing that Tadalafil 5 mg and Finasteride 5 mg relieved urinary symptoms more effectively than Finasteride alone and improved erections. These benefits were seen by week 4 and continued through weeks 12 and 26.

Potential side effects of Cialis and Finasteride

Taking the medicines together does not remove the individual side effects of either pill. Common Cialis side effects include a mild, temporary headache, muscle or back pain, dizziness, flushing, and nasal congestion. On the other hand, Finasteride is reported to trigger sexual side effects, including:

• Low Libido
• Erectile difficulties
• Reduced semen volume
• Ejaculation problems
• Breast tenderness or enlargement

These effects usually subside on their own when treatment is completed or discontinued as per the doctor’s guidance. A few studies have suggested that taking Cialis with Finasteride may reduce certain treatment-related sexual side effects, such as erectile difficulties, in some men. However, it will not reverse Low Libido or any other sexual symptoms of Finasteride.

Tips for safely taking Cialis and Finasteride together

Taking Cialis and Finasteride correctly can help reduce side effects and support consistent treatment. A few practical tips can make the combination safer and easier to manage:

• Follow the prescribed dosage: Take both the pills exactly as directed and at the recommended time. For BPH treatment, FDA labeling recommends both pills 5 mg once daily for around 26 weeks. Do not increase, skip, or double doses without consulting the doctor.
• Stay hydrated: Drink at least 3-4 liters of water throughout the day, especially if you feel dizzy or have a headache. However, avoid excessive fluids, especially close to bedtime, if frequent nighttime urination is an issue.
• Maintain a healthy lifestyle: Regular physical activity, a balanced diet, a healthy weight, and avoiding smoking can support overall prostate and cardiovascular health alongside prescribed medical treatment.
• Limit excessive alcohol intake: Excessive alcohol can increase Tadalafil’s blood-pressure-lowering effect and increase the risk of dizziness, headache, or faintness. Therefore, avoid or limit alcohol, particularly during the treatment.
• Monitor blood pressure: Cialis may lower blood pressure, and the effect is more pronounced with other medicines like nitrates or Riociguat. Contact a doctor if you repeatedly experience dizziness, lightheadedness, weakness, or fainting after taking the pill.
• Monitor side effects: Tell your doctor about persistent Finasteride or Cialis side effects. Additionally, seek immediate medical care for severe reactions such as fainting, sudden vision or hearing changes, or a prolonged painful erection (Priapism).

Who should not take Cialis and Finasteride together?

While you can take Cialis and Finasteride together, this combination is not safe for everyone. So, avoid using them together without medical approval if you:

• Take nitrates such as Isosorbide or Nitroglycerin.
• Take a Guanylate Cyclase (GC) stimulator, such as Riociguat.
• Have been advised to avoid intercourse because of heart issues.
• Have uncontrolled High Blood Pressure or very Low Blood Pressure.
• Have serious renal or liver impairment.
• Take another ED medication or certain blood pressure medicines.
• Have had an allergic reaction to either ingredient.
• Have had grapefruit juice or excessive alcohol.

Combining Tadalafil with other ED pills and some blood pressure medicines like Doxazosin, Prazosin, and Thiazide diuretics can significantly lower blood pressure.

Conclusion

There is no major Cialis and Finasteride interaction reported to date. In fact, your doctor can prescribe them together for better BPH control. Cialis can improve urinary symptoms quickly, while Finasteride gradually shrinks the prostate. Their combined use is also available as Entadfi, which contains 5 mg of each medication.

However, both medicines can cause side effects. Cialis can cause headache, flushing, or dizziness. On the other hand, Finasteride can cause sexual side effects like Low Libido, erection problems, or ejaculatory issues. While Cialis may improve erection difficulties linked with Finasteride in some cases, it doesn’t treat every Finasteride-related sexual effect.

Furthermore, tips to take combination safely include sticking to the prescribed dose, avoiding alcohol, and maintaining adequate hydration. Maintaining a healthy lifestyle and monitoring side effects can also enable a safe and effective treatment. People taking nitrates, Riociguat, or another ED pill should consult a doctor before using this combination for safety.