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Glossary Total Internal Reflection

light reflects entirely within a medium at a critical angle

Total Internal Reflection (TIR) occurs when a light wave traveling through a medium with a higher refractive index (like water or glass) hits the boundary of a medium with a lower refractive index (like air) at an angle greater than the critical angle, causing the light to be completely reflected back into the original medium rather than refracting through the boundary. This phenomenon is crucial in fiber optics, where it allows light to be efficiently transmitted over long distances with minimal loss.

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community Young guys 18-25, did hair loss destroy you mentally and affect your life? And if you did recover from it have you truly ever felt the same?

in Chat 146 upvotes 11 months ago

Hair loss greatly affects mental health and social life for young men. Treatments like finasteride, minoxidil, and hair transplants are common, with mixed success and ongoing self-esteem challenges.

community 5 months since I became obsessed with my hair

10 months ago

The user is experiencing hair regrowth and increased hair thickness after using supplements like biotin, zinc, selenium, and a complex with various natural ingredients, along with topical caffeine. They are considering using topical minoxidil and mesotherapy in the future.

community 📈 Solving for very low dose topical finasteride titration intervals

in Research/Science 30 upvotes 2 years ago

The conversation discusses using very low dose topical finasteride to achieve specific serum DHT reduction percentages. It concludes that finasteride dosage increases linearly between 5-30% DHT reduction but requires exponential increases for reductions up to 70%.

community Suffer so bad I want it to end

in Chat 111 upvotes 1 year ago

A 23-year-old is distressed about hair loss despite using dutasteride and oral minoxidil and is considering a hair transplant in Turkey. Many suggest therapy, hair systems, or acceptance, emphasizing mental health over appearance.

community Meta analysis of minoxidil only vs 5AR inhibitors

in Research/Science 58 upvotes 1 year ago

Oral dutasteride is the most effective for hair regrowth, followed by oral finasteride and minoxidil. Topical finasteride combined with minoxidil is recommended for those avoiding systemic DHT reduction.

community How significant is the difference between 0.5mg Dut and 1mg Fin?

in Finasteride/Dutasteride 11 upvotes 2 years ago

0.5mg dutasteride reduces scalp DHT more than 1mg finasteride, leading to better hair regrowth results. Users report significant improvement with dutasteride compared to finasteride.

community Y'all, we have got to come to a consensus on the specifics of microneedling.

27 upvotes 4 years ago

Microneedling can promote hair growth, but there is uncertainty about the best practices, including needle length, device, and session frequency. Users discuss using needle lengths between 0.5mm and 1.5mm, with some experiencing pinpoint bleeding, and emphasize the need for more reliable resources and guidelines.

community No longer have drive in the gym

in Chat 8 upvotes 4 months ago

The user lost gym motivation after taking finasteride for four months, possibly due to its effect on DHT levels. Suggestions include adjusting dosage, trying topical treatments, using caffeine, checking testosterone levels, and considering supplements like SSRIs or pregnenolone.

community Creatine? Experiences?What say YOU?

6 upvotes 6 months ago

Creatine may cause hair shedding in some individuals, but there is no strong scientific evidence linking it to hair loss. Many users report personal experiences of increased hair loss with creatine, while others see no effect; OP is considering creatine while using finasteride and topical minoxidil for hair loss.

community Does creatine really speed up hair loss if you have male pattern baldness?

132 upvotes 11 months ago

Creatine is not proven to cause hair loss, but some report increased shedding, especially with male pattern baldness. Finasteride or minoxidil are suggested to counteract potential hair loss while using creatine.

community 18M 8 months progress 40mg daily dut stack

in Progress Pictures 112 upvotes 1 year ago

An 18-year-old is using a high-dose hair loss treatment with 40mg daily dutasteride, finasteride, minoxidil, tretinoin, and topical bicalutamide. Despite health risk concerns, especially liver issues, they report hair regrowth progress and intend to continue the regimen.

community Dutasteride Infertility Debunked: Low T causes true infertility.

168 upvotes 1 year ago

Dutasteride and finasteride may temporarily affect semen quality but are unlikely to cause permanent infertility. The Kim et al. study is criticized for poor methodology, and many prefer hair retention over potential fertility concerns, using treatments like dutasteride, finasteride, and minoxidil.

community Publication concludes finasteride is a associated with a 60% risk of persistent sexual dysfunction.

345 upvotes 6 months ago

Finasteride is not linked to a 60% risk of persistent sexual dysfunction; this figure applies only to those already experiencing sexual issues. Most users do not have side effects, and the study's methodology is criticized for selection bias.

community Just Minoxidil 5% twice a day for 5 months

in Progress Pictures 584 upvotes 1 year ago

Significant hair regrowth was achieved using 5% Minoxidil twice daily and weekly microneedling with a 0.8 mm dermaroller over five months. Finasteride was not used due to concerns about side effects and availability in France.

community Almost 4 months of fin/min… quit waiting!!!

461 upvotes 1 year ago

A user shared their positive experience with hair regrowth using finasteride, minoxidil, dermastamping, and keto shampoo, noting significant improvement in four months without major side effects. They encouraged others to start treatment early and shared tips for application and tracking progress.

community Cardio for more than 60 minutes reduces DHT levels and improve hair growth

in Research/Science 126 upvotes 1 year ago

Long aerobic exercise (over 60 minutes) can reduce DHT levels and improve hair health. Some users discuss using Tadalafil (Cialis) to further reduce DHT after exercise, while others mention using treatments like Minoxidil, Finasteride, and RU58841 for hair growth.

community Attention Finasteride / Dutasteride and Your liver

374 upvotes 1 year ago

Finasteride may cause elevated liver enzymes, potentially leading to liver issues, though this is rare. Users should monitor liver function and consider topical alternatives if liver sensitivity occurs.

community Frequency/strength of topical minoxidil application

13 upvotes 2 years ago

The conversation discusses the effectiveness of Minoxidil (Min) for hair loss treatment. It concludes that applying a 5% solution once daily is sufficient, and applying it twice daily doesn't provide much more benefit. However, if a higher concentration is beneficial, it can be achieved by more frequent application.

community Whats up with all the dutasteride destroying hair posts

in Finasteride/Dutasteride 64 upvotes 3 years ago

User Basic_Football999 discusses concerns about negative dutasteride experiences. Replies suggest dutasteride is effective, but some users may have issues with dosing frequency or genetic factors affecting results.

community five yeras journey fighting hairloss

157 upvotes 1 month ago

The user has been battling hair loss for five years using Minoxidil, Finasteride, and Dutasteride. Despite some improvements, hair loss persists, and they are considering dietary changes and other treatments for seborrheic dermatitis and hyperhidrosis.

community We already know how to permanently fix hair loss. The science is done. The only thing missing is the funding to run one experiment.

in Technology 613 upvotes 4 months ago

A permanent hair loss solution could involve reprogramming hair follicles to resist DHT using mRNA and siRNA. However, high costs, safety concerns, and the pharmaceutical industry's preference for ongoing treatments over one-time cures are major obstacles, with finasteride and minoxidil remaining standard treatments.

community How long are Pelage going to milk the phase 2a results of PP405?

21 upvotes 8 months ago

PP405, a potential hair loss treatment, is facing delays in releasing Phase 2 results, causing frustration among users who compare it to past failed treatments. Despite skepticism, some remain hopeful about PP405's future, while others discuss alternative treatments like Clascoterone and its expected market release.

community Can we stop fear mongering with finasteride

in Finasteride/Dutasteride 285 upvotes 11 months ago

Finasteride is effective for hair loss but can cause sexual dysfunction and mental health issues in some users, leading to a polarized debate on its risks. Some switch to alternatives like Dutasteride or topical treatments to avoid side effects.

community I don’t understand this, is he equating taking Fin with being on HRT?

303 upvotes 1 year ago

The conversation is about using finasteride and testosterone replacement therapy (TRT) for hair loss and their role in gender-affirming care. It debates whether these treatments are considered hormone replacement therapy (HRT) and their implications for both cisgender and transgender individuals.

community Haunting study is making me considering cycling fin/dut

in Research/Science 158 upvotes 1 year ago

Concerns about the long-term effects of dutasteride and finasteride on fertility, with discussions on cycling these medications to mitigate risks. The conversation highlights skepticism about study methodologies and the importance of weighing treatment risks against potential fertility issues.

community Hair loss mental effect is so bad

in Satire 177 upvotes 1 year ago

Hair loss negatively affects mental health, causing anxiety and depression. Minoxidil and finasteride are discussed as treatments, but side effects and mental health concerns remain.

community The Fear of Oral Minoxidil is Overblown

272 upvotes 1 year ago

Low-dose oral minoxidil is a safe and effective hair loss treatment with fewer side effects than previously feared. Users often prefer it over topical minoxidil for better results, though some experience side effects like increased body hair and cardiovascular issues.

community New warning by FDA on topical finasteride

in Research/Science 194 upvotes 1 year ago

The FDA warned that topical finasteride can cause serious side effects like sexual dysfunction and brain fog, similar to oral finasteride. Compounded topical formulations pose additional risks due to lack of regulation.

community Has been on minoxidil for 5 years. Microneedling for 4 weeks no results.

in Minoxidil 27 upvotes 1 year ago

The user has used minoxidil for five years and added microneedling for four weeks without seeing results. They are considering a hair transplant but are advised that hair loss will persist without a DHT blocker.

community Did UCLA Just Cure Baldness? Check this Out!

in Research/Science 968 upvotes 1 year ago

UCLA's PP405 shows promise in reactivating dormant hair follicles for hair loss treatment but is still in clinical trials. Minoxidil and finasteride remain common treatments until PP405 becomes available.