Hair loss guides
Evidence-based guides on hair loss, the medications used to treat it, what to expect during treatment, and the lifestyle factors that affect hair health.
- Causes & biology
Vitamin D Deficiency and Hair Loss: What the Research Shows
Can low vitamin D cause hair loss? What the studies in men show, the blood levels that count as low, when testing makes sense, and why supplements are not a treatment for pattern hair loss.
- Causes & biology
Low Ferritin and Hair Loss: What Your Iron Result Means
Does low ferritin cause hair loss? What ferritin measures, why a normal lab range can still be low for hair, what the evidence shows in men, and why iron should not be taken without a test.
- Daily care & lifestyle
Can Dandruff Cause Hair Loss? How Flaking and Shedding Are Linked
Dandruff does not cause pattern baldness, but an inflamed, flaky scalp can add to shedding. How the two are linked, what anti-dandruff shampoos can and cannot do, and when to see a physician.
- Research & trends
What America Searched About Hair Loss in 2026: Five Shifts in the Data
US search data from early 2026 shows interest shifting from topical lotions toward pills, women driving the fastest growth, and rising local demand.
- Daily care & lifestyle
How to Use Your Curekey Dermaroller (Step-by-Step)
A practical guide to using a dermaroller with the FollicoreRX topical: hygiene, technique, frequency, and the 24-hour rule for tretinoin and dutasteride.
- Daily care & lifestyle
Does Hard Water Cause Hair Loss? What the Evidence Actually Shows
What research shows about mineral buildup, hair breakage, and the difference between damaged strands and true hair loss, plus what may actually help.
- Daily care & lifestyle
Scalp Massage for Hair Growth: Does It Actually Work?
The small studies behind the scalp massage trend, the plausible mechanism, what the research cannot show, and where gentle massage fits with treatment.
- Side effects & safety
Finasteride and Fertility: What Men Trying to Conceive Should Know
How finasteride may affect semen parameters and male fertility, why the 1 mg dose differs from 5 mg, how reversible changes are, and what to discuss first.
- Causes & biology
Does Thyroid Disease Cause Hair Loss?
Both an underactive and an overactive thyroid can trigger diffuse shedding. How thyroid hormone affects the hair cycle and which labs to ask for.
- Causes & biology
Seasonal Hair Loss: Is Shedding Really Worse in the Fall?
Why many people notice more shedding in late summer and fall, what the studies actually found, and how to tell a seasonal wave from loss worth evaluating.
- Daily care & lifestyle
Does Dyeing or Bleaching Hair Cause Hair Loss? What the Evidence Actually Shows
The difference between chemical breakage and follicle-level hair loss, when coloring or bleaching actually matters, and what drives pattern thinning.
- Causes & biology
Do Blood Pressure Medications Cause Hair Loss? Beta Blockers, ACE Inhibitors, and What the Evidence Shows
Whether beta blockers, ACE inhibitors, and other antihypertensives cause hair loss, what case reports and labels show, and what to do if you shed.
- Causes & biology
Does Testosterone Therapy (TRT) Cause Hair Loss? What Men Should Know
How TRT can accelerate pattern hair loss in genetically susceptible men, why delivery method matters, and how to protect your hair while on treatment.
- Daily care & lifestyle
Does Folic Acid Help With Hair Loss? What the Evidence Shows
What folate does for hair, when correcting a true deficiency may help with shedding, and why folic acid above normal levels is unlikely to regrow hair.
- Getting started
Can a Dermatologist Help With Hair Loss? When to See One
What a dermatologist does to evaluate hair loss, which cases need an in-person visit, and where physician-led telehealth fits for straightforward thinning.
- Daily care & lifestyle
Caffeine Shampoo for Hair Loss: Does It Actually Work?
What lab and human studies show about caffeine shampoos for pattern hair loss, why contact time matters, and where they fit next to proven treatments.
- Causes & biology
Does Smoking Cause Hair Loss? What the Evidence Actually Shows
Smoking is repeatedly associated with pattern hair loss in observational studies. What has been measured, the likely mechanisms, and how to weigh it.
- Daily care & lifestyle
Does Biotin Help With Hair Loss? What the Evidence Actually Says
Biotin is heavily marketed for thinning hair, but the evidence is narrow. When it may help, the lab-test interference risk, and what has more support.
- Causes & biology
Hair Loss After COVID or Illness: Why It Happens and When It Recovers
Heavy shedding a few months after COVID or another illness is usually telogen effluvium, a temporary stress response. How long it lasts and what to do.
- Side effects & safety
Minoxidil, Facial Hair, and Beard Growth: Side Effects and Reversibility
Why topical and oral minoxidil can cause unwanted facial and body hair, whether the growth reverses after stopping, and practical ways to reduce it.
- Causes & biology
Do Statins Cause Hair Loss? What the Evidence Shows
Hair loss is a rare and usually reversible side effect reported with statins. What the case reports and prescribing labels show and what to do if you shed.
- Causes & biology
Does Radiation Cause Hair Loss? What to Expect and When Hair Grows Back
Why diagnostic imaging does not cause hair loss, how radiation therapy to the head leads to anagen effluvium, and when regrowth is likely versus permanent.
- Daily care & lifestyle
Rosemary Oil for Hair Loss: Does It Actually Work?
The 2015 trial that compared rosemary oil with minoxidil, what the science does and does not show, and why it is seen as an adjunct, not a substitute.
- Causes & biology
Does Gabapentin Cause Hair Loss? What the Evidence Shows
Gabapentin is rarely linked to hair loss, and the evidence comes from a few case reports. What the literature shows and what to do if you shed on it.
- Medications
Spironolactone for Hair Loss in Women: How It Works and Who It Helps
How the anti-androgen spironolactone may help female pattern hair loss, who tends to benefit, typical dosing and timeline, and the monitoring involved.
- Causes & biology
Birth Control and Hair Loss: Why the Type of Progestin Matters
How hormonal contraceptives may affect hair, why a progestin's androgenic activity matters more than the method, and what to do if you shed after a change.
- Getting started
What Is the Best Hair Loss Treatment? How to Actually Choose
No single treatment suits everyone. How clinicians weigh your pattern of loss, how long it has progressed, and side-effect tolerance before choosing.
- Causes & biology
Do Antidepressants Cause Hair Loss? What the Evidence Shows by Drug Class
Which antidepressant classes are most often linked to shedding, how SSRI, SNRI, and bupropion hair loss works through telogen effluvium, and what to do.
- Causes & biology
Does Metformin Cause Hair Loss? What the Evidence Actually Shows
The link between metformin and hair shedding, the role of vitamin B12 depletion, and what to do if your hair is thinning while taking it for diabetes.
- Causes & biology
Does Wearing a Hat Cause Hair Loss? What the Evidence Actually Shows
Where the hat myth comes from, when headwear can cause real scalp problems like friction or folliculitis, and what actually drives pattern thinning.
- Daily care & lifestyle
Itchy Scalp and Hair Loss: What's the Connection?
Why an itchy scalp and shedding often appear together, the conditions that link them, from seborrheic dermatitis to inflammation, and when to worry.
- Causes & biology
Does Low Testosterone Cause Hair Loss? What the Evidence Actually Shows
Why follicle sensitivity to DHT matters more than total testosterone, whether low T causes scalp hair loss, and how replacement therapy fits in.
- Causes & biology
Postpartum Hair Loss: Timeline, What Helps, and When to Worry
Why postpartum shedding happens, the typical timeline for recovery, what may help, what is considered safe while breastfeeding, and when to ask a doctor.
- Causes & biology
What's New in Hair Loss Treatment Research: Stem Cells, JAK Inhibitors, Peptides, and More
Experimental hair loss treatments in clinical research, including JAK inhibitors, stem cell and exosome approaches, and topical anti-androgens.
- Daily care & lifestyle
Red Light Therapy (LLLT) for Hair Loss: Does It Actually Work?
What clinical trials show for low-level laser caps, combs, and helmets in pattern hair loss, the proposed mechanism, and how LLLT fits with medication.
- Causes & biology
Does Creatine Cause Hair Loss? What the Evidence Actually Shows
What the single 2009 creatine and DHT study really found, why it has not been replicated, and how to weigh the risk if you are prone to pattern hair loss.
- Causes & biology
What Is Androgenetic Alopecia? A Plain-English Guide to Pattern Hair Loss
The medical name for pattern hair loss explained in plain terms: what causes it, how it progresses in men and women, and which treatments have evidence.
- Causes & biology
Nutritional Deficiencies That Cause Hair Loss: Iron, Vitamin D, Zinc, B12, and More
Which deficiencies are actually linked to hair loss, including iron, vitamin D, zinc, and B12, what testing is useful, and when correcting one helps.
- Daily care & lifestyle
Ketoconazole Shampoo for Hair Loss: What the Studies Show
How ketoconazole shampoo may support pattern hair loss treatment, what the small trials measured, how often to use it, and how it fits with minoxidil.
- Causes & biology
Does Ozempic, Wegovy, or Mounjaro Cause Hair Loss? What the Evidence Shows
Why semaglutide, tirzepatide, and other GLP-1 medications are linked to shedding, the rapid weight loss mechanism behind it, and what to expect.
- Daily care & lifestyle
Do Hair Loss Shampoos Work? An Evidence-Based Look
A careful look at whether hair loss shampoos actually work, which ingredients have real clinical evidence, and which are mostly marketing claims.
- Side effects & safety
Is Finasteride Safe Long-Term? What 10+ Years of Data Show
What long-term studies of finasteride for pattern hair loss have measured, what physicians monitor during extended use, and how to think about years on it.
- Results & timelines
How Fast Does Minoxidil Work? A Realistic Timeline
What to expect on minoxidil from the first weeks through the one-year mark, including when early shedding is normal and when it may not be working.
- Getting started
Hair Loss Myths Debunked: What the Evidence Actually Says
The most common hair loss myths examined against the evidence, from inherited risk and hats to washing frequency, supplements, and treatment.
- Side effects & safety
Does Finasteride Cause Permanent Side Effects? What the Research Says
Whether finasteride side effects can persist after stopping, what controlled studies have found, what remains uncertain, and how to weigh the risk.
- Getting started
Early Signs of Hair Loss in Your 20s and 30s
How pattern hair loss usually begins in young adults, the subtle changes that appear before visible thinning, and why early evaluation matters at this age.
- Medications
Topical Finasteride: A Newer Alternative for Pattern Hair Loss
Topical finasteride delivers the medication directly to the scalp. How it works, what the evidence shows, and how it compares with the oral version.
- Medications
Combining Minoxidil and Finasteride: Why Pairing the Two Works Better Than Either Alone
Minoxidil and finasteride act on pattern hair loss through different mechanisms. What research shows about using them together as combination therapy.
- Medications
Dutasteride for Hair Loss: How It Works, Dose, Side Effects and Who It Suits
Dutasteride lowers DHT more than finasteride and is used off-label for male pattern hair loss. How it works, the usual dose, timeline, side effects, PSA tests and who should not take it.
- Medications
How Finasteride Treats Hair Loss: The Science, the Evidence, and What to Expect
Finasteride is one of two FDA-approved medications for pattern hair loss. How it lowers DHT, what trials show, and what to weigh before starting it.
- Results & timelines
What to Expect in Your First 6 Months of Hair Loss Treatment
A month-by-month look at starting treatment for pattern hair loss, including the early shedding phase, when to evaluate progress, and how to track results.
- Medications
How Minoxidil Treats Hair Loss: The Science, the Evidence, and What to Expect
Minoxidil is one of the most widely studied hair loss medications. How it acts on follicles, what clinical trials show, and what to expect when you start.
- Causes & biology
How the Hair Growth Cycle Works
A clear walkthrough of anagen, catagen, telogen, and exogen, and why understanding the hair cycle helps explain pattern hair loss and treatment timelines.
- Side effects & safety
Minoxidil Side Effects: Topical vs Oral, Shedding, and Facial Hair
Scalp itching, early shedding, unwanted facial hair, and the heart-rate or fluid changes seen with tablets. What is common and when to call a doctor.
- Getting started
How to Tell If You're Losing Hair (or Just Shedding Normally)
Practical signs that separate normal daily shedding from progressive pattern hair loss, what to check at the hairline and crown, and when to get assessed.
- Results & timelines
Why Hair Sheds When You First Start Treatment
Why early shedding often follows starting minoxidil or finasteride, what it may signal about the hair cycle resetting, and how long the phase lasts.
- Causes & biology
What DHT Is and Why It Causes Pattern Hair Loss
How 5-alpha-reductase converts testosterone to DHT, why genetically sensitive scalp follicles miniaturize in response, and what that means for treatment.
- Daily care & lifestyle
Do Hair Loss Supplements Work? An Evidence-Based Look
What clinical trials show for biotin, saw palmetto, marine collagen, and multivitamin blends sold for hair growth, and when a supplement may help.
- Getting started
Questions to Ask Before Starting Hair Loss Treatment
A practical checklist of questions to raise with a physician before starting prescription hair loss treatment: effectiveness, side effects, and stopping.
- Side effects & safety
Sexual Side Effects of Finasteride: What the Evidence Actually Shows
What placebo-controlled trials have measured for sexual side effects reported with finasteride, how often they occur, and what physicians watch for.
- Daily care & lifestyle
Scalp Care and Washing Routines for Thinning Hair
How shampoo frequency, scalp health, and styling habits interact with hair shedding, and what's worth doing versus what's marketing noise.
- Causes & biology
Stress and Hair Loss: Understanding Telogen Effluvium
How physical and emotional stress can trigger telogen effluvium, a temporary form of diffuse shedding, how it differs from pattern hair loss, and recovery.
- Getting started
What to Expect at Your First Telehealth Hair Loss Visit
A walkthrough of the medical questionnaire, physician review, and prescription steps at a typical telehealth hair loss assessment, with tips to prepare.
- Side effects & safety
When to Talk to a Doctor About Hair Loss Treatment Side Effects
A practical framework for telling common, manageable side effects from those that need a physician, for patients on minoxidil, finasteride, or dutasteride.
- Daily care & lifestyle
Diet and Hair Loss: What the Evidence Actually Supports
How protein, iron, vitamin D, zinc, and diet relate to hair health, with a clear view of which nutrition claims are well supported and which are not.
- Results & timelines
What 12 Months on Hair Loss Treatment Actually Looks Like
A realistic look at a full year of consistent minoxidil, finasteride, or both, including what clinical data shows about regrowth and why results vary.
Reference library
Browse the hair loss reference library
In-depth, encyclopedic coverage of the biology, stages, medications, and conditions, kept evergreen and updated.
Hair loss overview
The biology of pattern hair loss, how it progresses, and how it's treated.
Read moreCauses of hair loss
Genetic, hormonal, medical, nutritional, and stress-related causes.
Read moreFinasteride
How it works, dosing, timelines, side effects, and how it compares to dutasteride.
Read moreMinoxidil
Foam vs liquid, oral vs topical, shedding phases, and minoxidil for crown thinning.
Read moreDrug-induced hair loss
Medications that can cause or contribute to hair loss, and what to do about it.
Read moreAlternative treatments
Non-prescription approaches: red light therapy, PRP, microneedling, ketoconazole, and more.
Read moreHair loss in women
Female-pattern, postpartum, perimenopause, PCOS, thyroid, and treatment options for women.
Read moreHair loss in men
How male-pattern hair loss develops, progression by decade, and treatments with the strongest clinical evidence.
Read moreStages of hair loss
Norwood scale, receding temples, crown thinning, and diffuse pattern thinning explained.
Read more
Visible improvement can begin in 3–6 months
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