Post-finasteride syndrome
 | It has been suggested that this article be merged into Finasteride. (Discuss) Proposed since March 2021. |
Post-finasteride syndrome describes a range of sexual, physical and neurological side effects that are reported to persist and develop after cessation of the 5-alpha reductase inhibitors finasteride or dutasteride.[1] A 2019 editorial in the BMJ called post finasteride syndrome "ill defined and controversial".[2]
Preclinical evidence demonstrates interference by 5alpha-reductase inhibitors in sexual, cognitive and physical domains relevant to reported persistent symptoms.[1] The existence of the condition is often considered controversial, owing to both the underlying biological mechanism and the incidence of the condition being unclear.[3] A lack of clear diagnostic criteria and the variable reporting fraction in different health-care settings make the problem challenging to evaluate.[4]
Symptoms
Self-reported symptoms of post-finasteride syndrome include penile atrophy and tissue changes, decreased ejaculate volume and quality, libido loss, erectile dysfunction, loss of penile sensitivity, decreased orgasm sensation, dry skin, metabolic changes, muscle and strength loss, gynecomastia, depression, anxiety, panic attacks, insomnia, anhedonia, concentration problems, memory impairment and suicidal ideation.[4]
Cause
The rarity, variability and dose independence of the syndrome has been hypothesised to depend upon epigenetic phenotype. Finasteride-induced epigenetic changes in gene expression, including upregulation of the androgen receptor, may result in undesirable biological outcomes such as impairment of dopaminergic signalling and modulation of other neurotransmitter receptors, causing persistent or permanent adverse effects.[1]
Other scientists have suggested post-finasteride syndrome is a delusion or psychotic disorder, akin to other conditions such as Morgellons syndrome or multiple chemical sensitivity.[1]
Legal
Plaintiffs have filed over one thousand court cases against Merck over the effects of finasteride. Most were settled by 2018 when Merck paid a lump sum of US$4.3 million to be distributed. As of September 2019[update], 25 cases remained outstanding in the United States.[5]
In 2019 Reuters reported that faulty redactions in court documents revealed allegations from plaintiffs that Merck had known of persistent side effects in their original clinical trials but chose not to disclose them in warning labels.[5]
Research
Case-control study of symptomatic post-finasteride syndrome patients has revealed significantly higher expression of the androgen receptor in penile skin, markers of neuropathy of the pudendal nerve, and persistent alterations in levels of neuroactive steroids.[6]
References
- ^ a b c d Traish, Abdulmaged M. (2020-01-01). "Post-finasteride syndrome: a surmountable challenge for clinicians". Fertility and Sterility. 113 (1): 21–50. doi:10.1016/j.fertnstert.2019.11.030. ISSN 0015-0282. PMID 32033719.
- ^ Gray SL, Semla TP (August 2019). "Post-finasteride syndrome". BMJ. 366: l5047. doi:10.1136/bmj.l5047. PMID 31399423.
- ^ Gray, Shelly L.; Semla, Todd P. (2019-08-09). "Post-finasteride syndrome". BMJ. 366: l5047. doi:10.1136/bmj.l5047. ISSN 0959-8138. PMID 31399423.
- ^ a b Maksym, Radosław B.; Kajdy, Anna; Rabijewski, Michał (2019-10-02). "Post-finasteride syndrome – does it really exist?". The Aging Male. 22 (4): 250–259. doi:10.1080/13685538.2018.1548589. ISSN 1368-5538. PMID 30651009.
- ^ a b "U.S. court let Merck hide secrets about popular drug's risks". Reuters. Retrieved 2021-03-25.
these legal briefs filed by plaintiffs' lawyers allege that in revisions to the drug's original 1997 label, Merck understated the number of men who experienced sexual symptoms in clinical trials, and how long those symptoms lasted.
- ^ Patisaul, Heather B.; Belcher, Scott M. (2017-05-18). Receptor and Enzyme Mechanisms as Targets for Endocrine Disruptors. Vol. 1. Oxford University Press. doi:10.1093/acprof:oso/9780199935734.003.0005.