Does Levothyroxine Cause Hair Loss?

Written by Anjali Sayee

Levothyroxine is an oral medication used to treat hypothyroidism. Some research states it may cause hair loss (1). There are many drugs that cause hair loss by interfering with hair follicle growth. In this article, we understand the impact levothyroxine has on hair and what you can do to prevent any hair loss.

Does Levothyroxine Cause Hair Loss In Women And Children?

To understand if levothyroxine causes hair loss, we need to dive deep into the relation between thyroid dysfunction and hair loss. Thyroid dysfunctions are known to cause hair loss. Hypothyroidism (low thyroid functioning) causes the scalp to become oily. It also makes hair coarse and scanty, and may even lead to baldness. Excess thyroid function, on the other hand, causes hyperthyroidism that also makes hair fine and very scanty. Such thyroid imbalances can cause alopecia areata (2).

While levothyroxine is used to treat thyroid imbalances (and their associated side effects, like hair loss), it also may cause hair loss in some cases.

In a study, a 10-month infant diagnosed with hypothyroidism faced sudden diffuse alopecia on the scalp (3). The cause was found to be an overdose of levothyroxine, leading to an excessive thyroid function, causing hair loss. Hair loss occurred after two weeks of starting levothyroxine and ended a few days after the dosage was reduced. This shows that there needs to be an accuracy in the prescribed dosage. When ingested in the appropriate dosage, levothyroxine only balances the thyroid level without causing hair loss.

In another study conducted with 255 women, thyroxine (commonly levothyroxine) was shown to cause diffuse hair loss (4). This shows that anti-thyroid medication can cause drug-induced hair loss.

Drug-induced hair loss leads to either telogen or anagen effluvium (5). Telogen effluvium normally occurs two to four months after you start taking the drug (including levothyroxine). Anagen effluvium occurs within a few days or weeks from drug intake. These can lead to patterned or diffused hair loss and can be acute or chronic.

Hair loss is a common occurrence in pregnancy due to the change in hormone levels. Although it may cause hair loss, levothyroxine is one of the few medications safe for pregnant and nursing women (6).

Should You Discontinue Levothyroxine To Stop Hair Loss?

Since treatment with levothyroxine is lifelong, it cannot be discontinued. But depending on your thyroid levels, the dosage may be increased or decreased. Stopping anti-thyroid medication can have severe effects on the body. But there are some other treatment suggestions and lifestyle and dietary changes you can make to prevent hair loss.

Here are some tips you can try to prevent hair loss while taking levothyroxine.

How To Prevent Hair Loss In Women Who Take Levothyroxine

Levothyroxine medication is to be taken lifelong. But the dosage may be increased or decreased based on the hormone levels indicated in your blood test. If you take levothyroxine to regulate your thyroid levels but are experiencing hair loss, do not panic. Here are a few tips to help reduce such drug-induced hair loss.

  • You can try homemade hair masks made with natural ingredients like eggs, milk, oils, yogurt, and fenugreek seeds. These may stimulate hair growth and prevent hair loss.
  • Topical minoxidil can be used to treat hair loss and stimulate hair growth (8). Other medication like finasteride, topical steroid treatments, radiation therapy and tretinoin might help (9).
  • Aromatherapy and herbal treatments may also help reduce hair loss, and even stimulate hair growth (9).
  • Stress is another cause of hair loss. Improving your lifestyle to mitigate stress factors may help reduce hair loss. Exercise, meditate, and practice yoga or Pilates.
  • Consume more fruits and vegetables. These contain vitamins and minerals essential for hair growth (9).
  • Avoid crash diets or overeating.
  • Do not color your hair with regular hair dyes that use chemicals. Stop excess use of styling tools. Avoid going for hair chemical treatments too frequently.
  • Avoid hairstyles that pull on your hair.
  • Stop using shampoos and other hair products that contain chemicals, as they may cause an imbalance of the scalp and hair pH.

There is a specific method to diagnose hair loss caused by drugs. Know more in the next section.

Diagnosing Drug-Induced Hair Loss: When To See A Doctor

It is normal to lose 80 to 100 hair strands a day. But consult a doctor if you notice excessive hair loss. The doctor may perform a gentle pull test to confirm drug-induced hair loss (9). You may be asked to stop washing hair for five days before the test. After five days, a lock of hair is gently pulled at the ends to note the amount of hair loss occurring. Hair loss beyond 10% could be diagnosed as alopecia. The doctor might perform other tests to confirm drug-induced hair loss and may suggest any alternatives.


While levothyroxine may cause hair loss, it is often temporary, reversible, and treatable. You are more likely to notice hair growth once its dosage is reduced. However, since levothyroxine is to be taken for life in most cases, you also must focus on bettering your lifestyle and dietary habits. The right practices, if performed daily, can promote your hair and body health.

Recommended Articles


Articles on StyleCraze are backed by verified information from peer-reviewed and academic research papers, reputed organizations, research institutions, and medical associations to ensure accuracy and relevance. Read our editorial policy to learn more.

Was this article helpful?
The following two tabs change content below.
Anjali Sayee is a writer and an introvert. From studying Aeronautical Engineering and wanting to design her own airplane to writing articles on hairstyles, she has been on quite a journey. She believes that hair is one of the key factors that define a woman’s personality. To quote her, “What’s the first thing they do in the movies to show a personality change? Change the hair – because it has a life of its own.” She’s here to help you find the hairstyle you need. This bookworm is a self-professed Wholocker, a talented drummer, and an amateur photographer.