Hair Loss From Medication: Will It Grow Back?

How do medications cause hair loss?

Drugs can disrupt hair growth through two main mechanisms 1Ref 1Rebora A (2019).Telogen effluvium: a comprehensive review.Mechanism of telogen effluvium, drug-induced causes, and recovery timeline:

Telogen effluvium (the most common type): The medication stresses the follicle and pushes a large proportion of hairs into the resting phase simultaneously. About two to four months later, those hairs shed all at once — a sudden, diffuse loss across the scalp. Because the follicle is paused rather than damaged, it recovers once the disruption is removed.

Anagen effluvium: The medication interrupts the active growth phase directly — as happens with chemotherapy agents, which target rapidly dividing cells including those in hair follicles. Hair loss is more rapid and often more complete. Regrowth after chemotherapy typically begins within a few months of completing treatment.

Drug-induced hair loss is almost always diffuse (across the whole scalp) rather than patterned, which helps distinguish it from androgenetic alopecia.

Which medications are commonly linked to hair loss?

Many drug classes have been associated with hair loss, though individuals vary in whether they experience it and how severely 1Ref 1Rebora A (2019).Telogen effluvium: a comprehensive review.Mechanism of telogen effluvium, drug-induced causes, and recovery timeline2Ref 2American Academy of Dermatology (2024).Hair Loss Resource Center.Drug classes commonly associated with hair loss. Commonly implicated categories include:

• Anticoagulants (blood thinners): frequently cause telogen effluvium, often two to three months into use
• Antihypertensives: particularly beta-blockers and ACE inhibitors in some people
• Mood stabilizers and certain antidepressants: valproic acid (used for epilepsy and bipolar disorder) is a well-recognized culprit; some SSRIs are less commonly associated
• Retinoids (vitamin A derivatives): used for acne and skin conditions; diffuse shedding is a recognized side effect at higher doses
• Thyroid medications: both under- and over-treatment of thyroid disease can cause hair loss; getting the dose right is an important part of management
• Chemotherapy agents: the most dramatic and well-known form of drug-induced hair loss
• Some hormonal medications: including certain forms of hormonal contraception in people who are genetically susceptible to androgenetic alopecia

This list is not exhaustive. If you suspect a medication is contributing to your hair loss, bring it to your prescribing clinician.

What does recovery look like — and how long does it take?

For telogen effluvium from medications, shedding typically slows and stops within a few months of the medication being adjusted or discontinued. New growth often becomes visible at the hairline first, with fuller recovery over six to twelve months in most cases 1Ref 1Rebora A (2019).Telogen effluvium: a comprehensive review.Mechanism of telogen effluvium, drug-induced causes, and recovery timeline.

For anagen effluvium (including post-chemotherapy), hair may begin regrowing within weeks of completing treatment, with significant recovery by three to six months, though the texture or color of new hair may differ temporarily.

One important nuance: if you have underlying androgenetic alopecia (genetic pattern hair loss), a medication-induced shed may make that thinning more apparent — and that component will not fully reverse when the medication is stopped, because the underlying pattern loss was already present. A dermatologist can help you understand how much of your loss is drug-induced versus androgenetic 3Ref 3Adil A, Godwin M (2017).The effectiveness of treatments for androgenetic alopecia: A systematic review and meta-analysis.Distinguishing drug-induced shedding from underlying androgenetic alopecia when counseling on recovery expectations.

What to do — and what not to do

Do not stop or change a prescribed medication on your own because of hair loss. Many medications — anticoagulants, antiepileptics, antihypertensives — manage serious conditions, and stopping abruptly can be dangerous.

Instead: tell your prescribing clinician about the hair loss, ask whether it is consistent with what they have seen from that drug, and ask whether an alternative in the same class might be less likely to cause shedding. Your clinician may refer you to a dermatologist who can evaluate the scalp and, if appropriate, discuss supportive treatments while the medication continues.