Dutasteride

Dutasteride - Use | Dose | Side Effects

Dutasteride is a drug that is used to relieve the symptoms of prostate gland enlargement (BPH) and belongs to the family of drugs called inhibitors of testosterone 5-alpha reductase. Dutasteride reduces circulating levels of dihydrotestosterone (the main cause of BPH). Enlargement of the prostate causes the occurrence of the following symptoms:

  • Difficulty urinating
  • Frequent urination

Dutasteride alleviates these symptoms and improve quality of life in patients with BPH

Dutasteride reduces prostate size after only one month of the treatment with this drug. This drug reduces size of the prostate by 23.5% in a year, while after one month of treatment prostate size is reduced by 8%.

A few facts you need to know before you start taking Dutasteride

Dutasteride is intended for use only in men and should not be used in women and children.

This drug is metabolized through the liver so it cannot be used in patients with severe hepatic impairment.

Although according to the recommendations of the PIL, this drug should be very cautiously applied in patients with heart failure, the meta-analysis that included 12 randomized clinical studies has not established a correlation between Dutasteride and heart failure.1 According to some data, the risk of heart failure is significantly higher in patients taking a combination of dutasteride and some of the alpha blockers (usually tamsulosin). If you have heart disease, you should consult with your doctor before you start taking this medicine.

Dutasteride affects the level of prostate-specific antigen (PSA), which is very important for the diagnosis of prostate cancer. Dutasteride lowers the PSA level by 50% on average. Therefore, after 6 months from the initiation of therapy, PSA levels should be determined and then to be regularly monitored. Increased levels of PSA may indicate the occurrence of prostate cancer.

Although one study determined a higher incidence of prostate cancer in patients taking Dutasteride compared to the placebo group, mechanism responsible for that was not determined. It is assumed that there is only increased number of men who discovered prostate cancer in time, due to increased monitoring because of BHP. In the second study it was established that Dutasteride reduces the risk of carcinoma2

Dutasteride is absorbed through the skin into the blood, and in cases of capsules damage, women and children should not come into contact with the contents of the capsule.

Cases of breast cancer in men taking Dutasteride but without causal relation were reported. If you notice any changes in your breasts, tell your doctor immediately.

How should you take Dutasteride

Dutasteride is administered alone or in combination with an alpha-blocker (e.g. tamsulosin).

The recommended dose is 0.5 mg or one capsule a day, administered orally.

Do not chew the capsule because the contents of the capsule can damage the mucous membranes of the mouth. Swallow the capsule with a plain water.

Interactions

The following medicines may increase the concentration of Dutasteride and increase the risk of side effects:

  • Itraconazole, ketoconazole, fluconazole and other azoles (medicines used to treat fungal infections)
  • Ritonavir, indinavir and atazanavir (medicines used to treat AIDS)
  • Nefazodone (an antidepressant)
  • Amiodarone, nifedipine, diltiazem and verapamil (medicines for treatment of heart disease)
  • Chloramphenicol

So far no major interactions were reported.

Side effects

Dutasteride may cause the following side effects:

  • Heart failure
  • Swelling of the eyelids
  • Skin rash
  • Impotence, decreased libido, and gynecomastia (breast enlargement)

References

  1. NCBI link 1
  2. Nejm link 2