Finasteride and Dutasteride: A Doctor's Complete Guide
Dr Harry Hair
1,816 views
Finasteride and dutasteride are two of the most important treatments in hair restoration, but they are also surrounded by a bit of confusion, some straight up misinformation, and even some tribalism. Generally, they're not well understood.
In this video, I explain 5-alpha reductase inhibitors in depth: what they do, why targeting DHT helps pattern hair loss, the effectiveness of finasteride and dutasteride with data, how oral and topical finasteride compare, and what the evidence says about: side effects, fertility, mood, cognition, depression, suicidal ideation, and post-finasteride syndrome.
The aim is to move beyond the usual internet extremes and look at these medications as a real medical risk-benefit decision: effective for many people, but also not harmless, and best used with proper understanding, professional guidance, and a plan. Each decision is more individualised than a simple blanket rule for all.
I also introduce the concept of critical appraisal: how doctors and researchers judge the quality of evidence, why some studies deserve more caution than others, and how to avoid being misled by scary claims without dismissing genuine patient experiences.
Sources used to compile this video are included in the attached source list. https://docs.google.com/document/d/1m...
Timestamps
0:00 Introduction
2:38 What are 5-alpha reductase inhibitors?
4:52 Why DHT matters in male pattern hair loss
5:53 How effective is finasteride?
8:28 How does dutasteride compare?
11:37 What about topical finasteride?
14:53 Side effects: what the trial data show
16:27 Relative risk vs absolute risk
17:56 The nocebo effect
19:17 Fertility
20:49 PSA and other safety points
22:07 Mood, cognition and neurosteroids
23:43 What large population studies show
27:18 MHRA and EMA regulatory updates
29:04 Critical appraisal: how much salt should we take?
30:39 What is post-finasteride syndrome?
31:53 The FDA response to the PFS Foundation petition
33:28 Why the PFS evidence needs careful interpretation
36:23 What remains uncertain about persistent symptoms
37:53 Who should be more cautious with 5ARIs?
39:27 A safer prescribing plan
42:20 Early shedding after starting 5ARIs
43:54 What to do if side effects happen
44:24 Final takeaways
Disclaimer
This video is for educational purposes only and does not constitute personal medical advice. Do not start, stop, increase, reduce, or combine prescription medication based solely on this video. Decisions about finasteride, dutasteride, topical finasteride, minoxidil, or any other hair-loss treatment should be made with a qualified healthcare professional who can consider your diagnosis, medical history, mental health, fertility plans, other medications, and personal risk profile.
If you experience depressed mood, suicidal thoughts, significant side effects, or any concerning symptoms while taking a medication, stop and seek medical advice promptly. If you feel at immediate risk of harm, contact emergency services or a crisis support service in your country.
Use of AI and infographics
Some visual infographics in this video were created with the assistance of AI-based design tools. The scientific claims, numerical values, and study data shown in those graphics were taken from real sources, including peer-reviewed studies, prescribing information, and regulatory documents. These figures were manually checked against the original sources before being included. AI was used as a visual and production aid, not as a substitute for source review, clinical judgement, or evidence appraisal.
10 Comments
Finasteride and Dutasteride: A Doctor's Complete Guide
Dr Harry Hair
1,816 views
Finasteride and dutasteride are two of the most important treatments in hair restoration, but they are also surrounded by a bit of confusion, some straight up misinformation, and even some tribalism. Generally, they're not well understood.
In this video, I explain 5-alpha reductase inhibitors in depth: what they do, why targeting DHT helps pattern hair loss, the effectiveness of finasteride and dutasteride with data, how oral and topical finasteride compare, and what the evidence says about: side effects, fertility, mood, cognition, depression, suicidal ideation, and post-finasteride syndrome.
The aim is to move beyond the usual internet extremes and look at these medications as a real medical risk-benefit decision: effective for many people, but also not harmless, and best used with proper understanding, professional guidance, and a plan. Each decision is more individualised than a simple blanket rule for all.
I also introduce the concept of critical appraisal: how doctors and researchers judge the quality of evidence, why some studies deserve more caution than others, and how to avoid being misled by scary claims without dismissing genuine patient experiences.
Sources used to compile this video are included in the attached source list. https://docs.google.com/document/d/1m...
Timestamps
0:00 Introduction
2:38 What are 5-alpha reductase inhibitors?
4:52 Why DHT matters in male pattern hair loss
5:53 How effective is finasteride?
8:28 How does dutasteride compare?
11:37 What about topical finasteride?
14:53 Side effects: what the trial data show
16:27 Relative risk vs absolute risk
17:56 The nocebo effect
19:17 Fertility
20:49 PSA and other safety points
22:07 Mood, cognition and neurosteroids
23:43 What large population studies show
27:18 MHRA and EMA regulatory updates
29:04 Critical appraisal: how much salt should we take?
30:39 What is post-finasteride syndrome?
31:53 The FDA response to the PFS Foundation petition
33:28 Why the PFS evidence needs careful interpretation
36:23 What remains uncertain about persistent symptoms
37:53 Who should be more cautious with 5ARIs?
39:27 A safer prescribing plan
42:20 Early shedding after starting 5ARIs
43:54 What to do if side effects happen
44:24 Final takeaways
Disclaimer
This video is for educational purposes only and does not constitute personal medical advice. Do not start, stop, increase, reduce, or combine prescription medication based solely on this video. Decisions about finasteride, dutasteride, topical finasteride, minoxidil, or any other hair-loss treatment should be made with a qualified healthcare professional who can consider your diagnosis, medical history, mental health, fertility plans, other medications, and personal risk profile.
If you experience depressed mood, suicidal thoughts, significant side effects, or any concerning symptoms while taking a medication, stop and seek medical advice promptly. If you feel at immediate risk of harm, contact emergency services or a crisis support service in your country.
Use of AI and infographics
Some visual infographics in this video were created with the assistance of AI-based design tools. The scientific claims, numerical values, and study data shown in those graphics were taken from real sources, including peer-reviewed studies, prescribing information, and regulatory documents. These figures were manually checked against the original sources before being included. AI was used as a visual and production aid, not as a substitute for source review, clinical judgement, or evidence appraisal.