Dutasteride

Registered South African indications:

• Benign prostatic hyperplasia

Contraindications

South African recommendations

• Known hypersensitivity to dutasteride, other 5α-reductase inhibitors, or to any of the excipients
• Women
• Children

Recommendations in other jurisdictions

• Hypersensitivity to the active substance or to any of the excipients
• Hypersensitivity to dutasteride, other 5-alpha reductase inhibitors, or any of the other excipients
• Women
• Children
• Adolescents
• Severe hepatic impairment

Cautions

• Renal impairment
• Hepatic impairment (South African recommendations)
• Mild to moderate hepatic impairment (Recommendations in other jurisdictions)

Forms avail. in SA and covered in this monograph: cap

Dosages below include:

• South African registered indications and dosages

South African registered indications and dosages

Benign prostatic hyperplasia

• Oral (cap): 0.5mg, dly; Minimum duration of treatment: 6 months

Although an improvement may be observed at an early stage, treatment for at least 6 months may be necessary in order to assess objectively whether a satisfactory response to the treatment can be achieved

The capsules should be swallowed whole. Dutasteride may be taken with or without food

Contraindicated

Pregnancy

• Not indicated for use in women: Contraindicated
• As with other 5-alpha reductase inhibitors, dutasteride inhibits the conversion of testosterone to dihydrotestosterone and may, if administered to a woman carrying a male foetus, inhibit the development of the external genitalia of the foetus
• Small amounts of dutasteride have been recovered from the semen in subjects receiving dutasteride 0.5 mg per day
• It is not known whether a male foetus may be adversely affected if his mother is exposed to the semen of a patient being treated with dutasteride, the risk of which is greatest during the first 16 weeks of pregnancy
• As with all 5-alpha reductase inhibitors, when the patient's partner is or may potentially be pregnant it is recommended that the patient avoids exposure of his partner to semen by use of a condom

Breastfeeding

• Not indicated for use in women: Contraindicated
• It is not known whether dutasteride is excreted in human milk

Renal Impairment

• Caution; no information available

Hepatic Impairment

South African recommendations

• Caution; no information available
  The effect of hepatic impairment on dutasteride pharmacokinetics has not been studied

Recommendations in other jurisdictions

• Mild to moderate: Caution; no information available
  The effect of hepatic impairment on dutasteride pharmacokinetics has not been studied so caution should be used in patients with mild to moderate hepatic impairment
• Severe: Contraindicated

Elderly

• No dose adjustment recommended 

Porphyria Information

• Probably not porphyrinogenic (PNP)

Drugs in Sport

• Permitted - No warnings

Central Nervous System Disorders

• Depressed mood

Genitourinary Disorders

• Impotence
• Altered libido
• Ejaculation disorders
• Testicular pain
• Testicular swelling

Endocrine and Metabolic Disorders

• Breast disorders

Skin and Subcutaneous Tissue Disorders

• Pruritus
• Urticaria
• Alopecia
• Hypertrichosis

Immune, Blood and Lymphatic System Disorders

• Allergic reactions
• Localised oedema
• Angioedema

• CYP3A4 inhibitors
• P-glycoprotein inhibitors

None routine

Dutasteride is a dual inhibitor of 5 alpha reductase. It inhibits both type 1 and type 2 5-alpha reductase isoenzymes which are responsible for the conversion of testosterone to 5α-dihydrotestosterone (DHT). DHT is the androgen primarily responsible for hyperplasia of glandular prostatic tissue.

Capsule 0.5mg

• Avodart (GSK) originator
• Zedrast ( Zydus Healthcare)