What drug makes your hair come out? A guide to medication-induced hair loss

October 11, 2025 •

4 min read

Medication-induced hair loss is a recognized side effect for numerous drugs, with estimates suggesting that hundreds of common prescriptions can trigger this distressing condition. Understanding what drug makes your hair come out involves identifying the specific pharmacological agents and mechanisms that interfere with the natural hair growth cycle.

Quick Summary

A wide variety of medications, from chemotherapy agents to common prescriptions like antidepressants and blood thinners, can cause hair loss. This side effect, known as drug-induced alopecia, most often results from anagen or telogen effluvium, interfering with the hair's natural growth cycle. Hair loss is often reversible upon adjusting or discontinuing the medication under a doctor's guidance.

Key Points

Chemotherapy is a major cause of hair loss: Chemotherapy drugs target fast-dividing cells, including hair follicle cells, leading to rapid hair loss called anagen effluvium.
Blood thinners and other common drugs can cause shedding: Many medications, like warfarin and heparin, can cause a delayed, widespread hair shedding known as telogen effluvium.
Psychiatric medications are known culprits: Antidepressants, mood stabilizers (e.g., lithium), and other psychiatric drugs can induce hair loss by disrupting the hair cycle.
Hormonal shifts can cause hair loss: Hormonal medications such as birth control pills, HRT, and testosterone-based products can trigger hair thinning or loss.
Do not stop medication without a doctor's advice: Abruptly discontinuing necessary medication can be dangerous. Always consult a healthcare provider to explore safer alternatives or management strategies for hair loss.
Drug-induced hair loss is often reversible: In most cases, hair will grow back after stopping or adjusting the offending medication, though it may take several months.
Folic acid can help with methotrexate side effects: Taking folic acid supplements can help mitigate hair loss caused by the arthritis drug methotrexate.

The Hair Growth Cycle: Two Main Mechanisms of Drug-Induced Alopecia

Medication-induced alopecia, the medical term for drug-related hair loss, primarily occurs through two distinct mechanisms that disrupt the hair growth cycle. A typical hair growth cycle involves a growing phase (anagen), a transitional phase (catagen), and a resting phase (telogen), after which the hair is shed. Medications can interrupt this process in one of two ways:

Anagen Effluvium

This type of hair loss affects hair follicles in their active growth phase (anagen) and typically results in rapid, widespread shedding. It is most famously associated with chemotherapy because these drugs target and destroy fast-dividing cells, which include the cells within hair follicles. Hair loss from anagen effluvium can be severe, causing not only scalp hair to fall out but also body hair, eyelashes, and eyebrows. The hair may break off rather than shed from the root, leading to significant thinning or complete baldness within weeks of starting treatment.

Telogen Effluvium

Far more common than anagen effluvium, telogen effluvium occurs when a medication or other stressor causes a large number of hair follicles to enter the resting phase (telogen) prematurely. Since the telogen phase lasts for several months, the resulting hair shedding becomes noticeable two to four months after starting the medication. This hair loss is typically temporary and characterized by widespread thinning rather than bald patches. Many different drug classes can trigger this process, including anticoagulants, antidepressants, and hormone therapies.

Common Medications That Cause Hair Loss

Many prescription drugs can cause hair loss as a side effect. The severity and likelihood depend on the specific drug, dosage, and individual susceptibility.

Chemotherapy and Cancer Treatments

These are the most well-known culprits. Examples of chemotherapy drugs with a high likelihood of causing hair loss include:

Doxorubicin
Docetaxel
Paclitaxel
Cyclophosphamide

Targeted therapies and hormonal treatments for cancer may also cause hair thinning, though typically less severely than conventional chemotherapy.

Blood Thinners (Anticoagulants)

Anticoagulant medications are known to trigger telogen effluvium. Examples include:

Warfarin (Coumadin)
Heparin

Antidepressants and Mood Stabilizers

A range of psychiatric medications, particularly those that affect hormone or stress levels, can lead to hair shedding.

SSRIs (e.g., fluoxetine, sertraline)
Mood Stabilizers (e.g., lithium, valproic acid)
Bupropion

Hormonal Medications

Changes in hormone levels can profoundly impact the hair cycle.

Birth control pills: Hair loss is more likely when starting or stopping them.
Hormone replacement therapy (HRT): Can trigger hair thinning in some women.
Anabolic steroids and testosterone: These can accelerate male or female pattern baldness.

Arthritis Medications

Certain drugs used for inflammatory conditions suppress the immune system and can affect hair follicles.

Methotrexate: The hair loss may be mitigated by taking folic acid supplements.
Leflunomide (Arava)

Other Drug Classes

Retinoids: Used for severe acne and psoriasis, like isotretinoin (Accutane).
High Blood Pressure Medications: Including beta-blockers (e.g., metoprolol) and ACE inhibitors.
Cholesterol-Lowering Drugs: Such as gemfibrozil (Lopid).
High Doses of Vitamin A: Can trigger excessive shedding.
NSAIDs: Overuse of nonsteroidal anti-inflammatory drugs like naproxen can affect the hair cycle.

Comparison of Drug-Induced Alopecia


Feature	Anagen Effluvium	Telogen Effluvium
Onset	Rapid, within days to weeks of starting medication.	Delayed, becomes noticeable 2-4 months after starting medication.
Mechanism	Targets rapidly dividing hair follicle cells, causing hair to break or stop growing.	Prematurely shifts hair follicles from the growth phase into the resting phase.
Severity	Often severe and widespread, potentially affecting all body hair.	Typically causes widespread thinning, not total baldness.
Reversibility	Usually reversible once treatment ends, though texture or color may change.	Reversible; hair growth typically returns to normal after the drug is stopped.
Common Culprits	Chemotherapy agents.	Anticoagulants, antidepressants, blood pressure medications, hormonal drugs.

What to Do If You Suspect Drug-Induced Hair Loss

If you believe a medication is causing hair loss, it is crucial to consult your doctor. They can determine if the drug is the culprit and safely explore alternatives.

Never stop medication abruptly

Unless your doctor advises you to do so, do not stop taking a prescribed medication. For serious conditions, the benefits of treatment often outweigh the side effect of hair loss. Your physician can assess the risk-benefit ratio.

Explore alternatives

Your doctor may be able to lower your dosage, switch you to a different drug within the same class, or prescribe an alternative with a lower risk of hair loss.

Support hair regrowth

For temporary hair loss, your hair will typically regrow on its own once the causative drug is stopped. Your doctor might also recommend a supplement like folic acid if you are on methotrexate. Topical minoxidil (Rogaine) can be used to stimulate regrowth in some cases.

Cope during treatment

For conditions like chemotherapy-induced hair loss, scalp cooling techniques can sometimes minimize shedding. Wigs, scarves, or hats are other options to manage appearance during treatment.

Conclusion

Drug-induced hair loss is a potential side effect of many common and necessary medications, not just chemotherapy. By understanding the underlying mechanisms of anagen and telogen effluvium, patients can better grasp the cause of their hair loss. While a stressful experience, this form of hair loss is most often temporary. The key to managing it lies in open communication with a healthcare provider to safely adjust treatment and support hair regrowth after the offending drug is discontinued. With professional guidance, it is possible to navigate this side effect while prioritizing overall health.

Learn more about managing drug side effects with resources from the American Hair Loss Association.

Frequently Asked Questions

Medication can cause two main types of hair loss: anagen effluvium, a rapid and severe form, and telogen effluvium, a more common and delayed hair shedding.

In most cases, drug-induced hair loss is temporary. Once you stop taking the medication (under a doctor's supervision), your hair should start to grow back within several months.

Yes, some blood pressure medications, including beta-blockers and ACE inhibitors, have been linked to hair loss, often through a telogen effluvium mechanism.

No, not all chemotherapy drugs cause hair loss. The likelihood and severity depend on the specific drug, dosage, and combination of treatments. Some drugs are more likely to cause significant hair loss than others.

For anagen effluvium (e.g., chemotherapy), hair loss can begin within days to weeks. For telogen effluvium, hair shedding is typically delayed and becomes noticeable two to four months after starting the drug.

Consult your doctor immediately. Do not stop taking your medication on your own. Your doctor can help you determine the cause, adjust your dosage, or find an alternative treatment.

Topical minoxidil may help stimulate hair regrowth in some cases of drug-induced hair loss. However, you should discuss this with your doctor before starting treatment.