| name | Dutasteride (Avodart) |
| classification | 5-alpha reductase inhibitor |
| pharmacokinetics | | absorption | Well absorbed after oral administration, reaching peak plasma concentrations within 1-4 hours. | | distribution | High protein binding (>99%). Primarily metabolized by the liver. | | metabolism | Metabolized extensively in the liver, primarily by the CYP3A4 isoenzyme. | | excretion | Eliminated primarily in the feces as metabolites. The active metabolite is also slow to clear from the body. |
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| suggested dosage | For benign prostatic hyperplasia (BPH), the typical dose is 0.5 mg orally once daily. For male pattern hair loss, the dosage may be higher, but this is not standard clinical practice. |
| indications | | 1 | Benign prostatic hyperplasia (BPH): Used to reduce urinary obstruction symptoms and improve urinary flow. | | 2 | Male pattern hair loss (androgenetic alopecia): It's less often prescribed for this indication. |
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| safety in pregnancy | **Category X**: Should not be used in pregnant women or women who may become pregnant. It is known to cause abnormalities in developing male fetuses. Dutasteride should be avoided in pregnant women and women of childbearing potential who are not using adequate contraception. |
| safety in breastfeeding | Not recommended. It is unknown if the drug is excreted in breast milk. |
| side effects | | 1 | Decreased libido | | 2 | Erectile dysfunction | | 3 | Ejaculatory dysfunction | | 4 | Breast tenderness or enlargement (gynecomastia) | | 5 | Back pain | | 6 | Headache | | 7 | Muscle weakness or aches | | 8 | Fatigue | | 9 | Dizziness | | 10 | Nausea | | 11 | Diarrhea | | 12 | Skin rash |
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| alternatives | |
| contraindications | | 1 | Known hypersensitivity to dutasteride or any of the inactive ingredients | | 2 | Pregnancy (Category X) | | 3 | Women of childbearing potential not using adequate contraception | | 4 | Active liver disease |
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| interactions | | 1 | CYP3A4 inhibitors (e.g., ketoconazole, erythromycin) may increase dutasteride levels, potentially increasing the risk of side effects | | 2 | CYP3A4 inducers (e.g., rifampin, St. John's Wort) may decrease dutasteride levels, potentially reducing efficacy. | | 3 | Use with other medications affecting the prostate, particularly alpha-blockers, should be approached cautiously. |
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| warnings and precautions | | 1 | Monitoring of liver function is usually not needed, but can be considered. | | 2 | Patients should be advised to report any signs of breast changes, muscle pain, or other unusual symptoms to their physician promptly. | | 3 | The potential for long-term side effects is not fully known. | | 4 | Dutasteride should not be used in children |
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| additional informations | | 1 | This drug is a prescription-only medication. Patients should follow their doctor's instructions carefully for dosage and usage. | | 2 | It can take several months to see the full benefit of dutasteride for BPH. | | 3 | The risk of side effects like erectile dysfunction and decreased libido is greater with dutasteride than with other similar medications, particularly compared to Tamsulosin. |
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| patient specific considerations | | age | 25 years - Relevant to potential long-term use and potential for drug-related adverse effects. | | weight | 70kg - Likely to have standard clearance for dutasteride. |
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