Avodart Autoimmune Disease Considerations: What Clinicians and Patients Need to Know

At a glance

• FDA-approved use / symptomatic BPH in men with an enlarged prostate; hair loss is off-label [1]
• Autoimmune contraindication / none listed; label contraindications are pregnancy and prior serious hypersensitivity [1]
• DHT effect / median serum DHT fell 85% after 1 week and 90% after 2 weeks on 0.5 mg daily [1]
• Testosterone effect / median rose about 19% to 26% but stayed within the physiologic range [1]
• Half-life / about 5 weeks at steady state; detectable for up to 4 to 6 months after stopping [1]
• Labeled hypersensitivity / rash, itching, hives, localized edema, serious skin reactions, angioedema [1]
• Postmarketing reports / male breast cancer, depressed mood, testicular pain and swelling [1]

Does the Avodart label list autoimmune disease as a contraindication?

No. The label's contraindications are pregnancy and a previous clinically significant hypersensitivity reaction, such as serious skin reactions or angioedema, to Avodart or another 5-alpha reductase inhibitor [1]. That is a labeling fact, not a study result in people with autoimmune disease.

What does dutasteride do to DHT and testosterone?

Dutasteride inhibits both type 1 and type 2 5-alpha-reductase and does not bind the androgen receptor [1]. On 0.5 mg daily, median serum DHT fell 85% after 1 week, 90% after 2 weeks, and 94% at 1 year [1]. Median serum testosterone rose about 19% to 26% but remained within the physiologic range [1]. Separately, sex hormones influence immune responses, and autoimmune diseases are more common in women [2].

Is drug-induced lupus linked to dutasteride?

Drug-induced lupus is a lupus-like syndrome triggered by a medication. The Avodart label's postmarketing reports name hypersensitivity reactions (rash, itching, hives, localized edema, serious skin reactions, angioedema), male breast cancer, depressed mood, testicular pain and swelling [1]. Drug-induced lupus is not named among them [1].

What interactions matter with immunosuppressant drugs?

The label advises caution with potent, chronic CYP3A4 inhibitors such as ritonavir; the effect of potent CYP3A4 inhibitors on dutasteride has not been studied [1]. The drug interactions section also covers alpha-adrenergic antagonists, verapamil and diltiazem, cholestyramine, digoxin and warfarin [1]. It does not list methotrexate, hydroxychloroquine, tacrolimus, cyclosporine, sirolimus or biologic drugs such as adalimumab or secukinumab [1]. A missing listing does not mean the combination was studied.

What labeled safety concerns apply?

The label's most common adverse reactions are impotence, decreased libido, ejaculation disorders and breast disorders [1]. The label says sexual adverse reactions may persist after discontinuation and that the role of dutasteride in that persistence is unknown [1]. Avodart is not indicated for use in women and is contraindicated in pregnancy [1].

Frequently asked questions

›Is dutasteride contraindicated in autoimmune disease?

No. The Avodart label's contraindications are pregnancy and previous clinically significant hypersensitivity to Avodart or another 5-alpha reductase inhibitor [1]. Autoimmune disease is not listed [1].

›Does dutasteride cause lupus?

The Avodart label's postmarketing reports name hypersensitivity reactions, male breast cancer, depressed mood, testicular pain and swelling, and do not name drug-induced lupus [1].

›Does dutasteride interact with methotrexate?

The drug interactions section does not list methotrexate. It advises caution with potent, chronic CYP3A4 inhibitors such as ritonavir and states that the effect of potent CYP3A4 inhibitors on dutasteride has not been studied [1].

›Can women take dutasteride?

Avodart is not indicated for use in women and is contraindicated in pregnancy [1]. The label says pregnant women should not handle Avodart capsules because dutasteride can be absorbed through the skin and could harm a male fetus [1].

›How long does dutasteride stay in the body?

The terminal half-life is about 5 weeks at steady state [1]. After the last dose, serum levels can remain detectable above 0.1 ng/mL for up to 4 to 6 months [1].

References

1. U.S. National Library of Medicine, DailyMed. Avodart (dutasteride) soft gelatin capsules, Waylis Therapeutics prescribing information. Avodart (dutasteride) soft gelatin capsules, Waylis Therapeutics label
2. Bouman A, Heineman MJ, Faas MM. Sex hormones and the immune response in humans. Hum Reprod Update. 2005;11(4):411-23. Sex hormones and the immune response in humans