Can Mounjaro cause hair loss? How to avoid & stop it

Monday, October 26, 2026

When starting Mounjaro for weight loss, one thing you may not expect to lose is your hair.

Mounjaro can cause hair loss. It is a common side effect of Tirzepatide, the active ingredient in Mounjaro injections, but the good news is that it is usually mild and temporary. Most people who experienced hair loss in clinical trials recovered while still on treatment (1).

In some cases, you may also be able to reduce the risk of hair loss on Mounjaro by making sure you are eating enough, getting the nutrients you need and moving through your dose schedule gradually. Here, we explain how to reduce the risk and what to do if shedding has already started.

Learn more about Mounjaro for weight management through Oxford Online Pharmacy.

In this article:

Is hair loss a side effect of Mounjaro?
Why does Mounjaro cause hair loss?
Is Mounjaro hair loss permanent?
How to prevent Mounjaro hair loss
How to stop hair loss on Mounjaro
Mounjaro and hair loss FAQs
When to talk to your doctor or pharmacist about Mounjaro and hair loss

Is hair loss a side effect of Mounjaro?

Hair loss is a common side effect of Mounjaro, affecting between 1 in 100 and 1 in 10 people (1).

In clinical trials, around 5% of people taking Tirzepatide reported hair loss, compared to 1% of people taking a placebo. Most cases were mild, temporary, and improved while still taking Mounjaro. No participants taking Tirzepatide stopped the medicine or left the studies because of hair loss (1).

Women may be more likely to experience hair loss with Mounjaro (2). Trial data reported hair loss in 7.1% of females compared with 0.5% of males (2). Research into weight-loss-related hair loss also found that affected women had lost less weight on average than affected men (3).

Hair loss is a recognised Mounjaro side effect based on these trial findings, but it doesn’t mean you will necessarily experience it. Everyone tolerates the medicine differently.

If you are experiencing hair loss we have a wide range of male hair loss treatments and have just launched our female hair loss range.

Why does Mounjaro cause hair loss?

We do not know exactly why some people get hair loss while taking Mounjaro for weight loss.

There is currently no evidence that Tizepatide directly damages hair follicles or directly changes the normal hair growth cycle. Research suggests that hair loss on Mounjaro may instead be linked to changes that happen during treatment, although the exact cause is still being studied (2).

Possible contributors include:

Losing a lot of weight quickly
Eating less than usual
Not getting enough of certain nutrients

The type of hair loss thought to be involved with these changes is telogen effluvium (4).

Hair normally moves through a cycle of growth and rest, but in telogen effluvium, physiological changes or stress on the body can temporarily disrupt the cycle. More hairs than usual enter the resting phase around the same time and are all shed together several months later (4).

Hair loss can also happen for completely unrelated reasons at the same time as taking Mounjaro.

Weight loss can disrupt the normal hair cycle

Substantial weight loss is a known trigger of telogen effluvium.

One study of people who developed telogen effluvium after weight loss found that they had lost an average of 15.2% of their starting body weight (3). This does not mean there is a set weight-loss threshold for hair shedding, but it supports rapidly losing a lot of weight as a possible trigger.

Because Mounjaro can cause average weight loss of up to 20.9%, this is one possible explanation for hair shedding during treatment (5). This theory is further supported by research that found people who developed hair loss on Tirzepatide tended to have a lower follow-up BMI than those who did not, although this in itself still does not prove that weight loss is the cause (6).

Telogen effluvium commonly becomes noticeable around three months after the trigger, so you may not get hair loss as a symptom until you have already been using Mounjaro for some time (4).

Nutritional deficiencies can affect hair growth

Mounjaro reduces appetite, so you may eat much less than before. If your diet becomes very limited, it can be harder to get enough of the nutrients needed for normal hair growth.

More specifically, low protein intake and iron deficiency have both been linked with telogen effluvium and temporary hair shedding. Other deficiencies like zinc deficiency and vitamin B12 deficiency may affect hair growth too, although the evidence is less consistent (7).

While nutrition can impact hair loss, not everyone who sheds hair on Mounjaro necessarily has a deficiency. However, if you are regularly skipping meals, eating very small amounts or struggling to maintain a balanced diet, it may be worth looking closely at your diet or getting blood tests to see if you are deficient in anything.

Mounjaro may not be the only possible cause

Hair loss that starts while you are taking Mounjaro is not necessarily caused by the medicine.

In the Mounjaro weight-management trials, 1% of people taking a placebo also reported hair loss, which shows that some hair loss seen during treatment may have happened anyway (1). There are many other possible causes of hair loss, including:

Stress-related hair loss
Illness
Thyroid problems
Hormonal changes
Postpartum hair loss
Other medicines

Some of these can look very similar to hair loss linked with weight loss. For example, stress, illness and postpartum changes are all triggers for telogen effluvium, causing the same general thinning or increased shedding across the scalp that some people see with Mounjaro (4).

Other types of hair loss may look different. For example, round or patchy bald areas can happen with alopecia areata, while gradual thinning at the crown or hairline is typical of pattern hair loss. Scalp redness, scaling, pain or broken hairs may point to another cause.

If your hair loss is severe, causes bald patches, affects your scalp, or continues for longer than expected, speak to a healthcare professional. They can check whether something else could be contributing and whether you may benefit from hair loss treatment.

Is Mounjaro hair loss permanent?

Mounjaro-related hair loss is not usually permanent. In telogen effluvium, the hair follicles are not permanently damaged, and hair typically grows back once the trigger has resolved (4).

You do not necessarily need to stop Mounjaro for this to happen. In clinical trials, most people who experienced hair loss saw improvements while they were still taking Tirzepatide (1). If rapid weight loss, reduced food intake or nutritional gaps have caused the shedding, hair growth may recover as these factors become more stable, even while you continue treatment.

The hair recovery process can take a while. The shedding phase of telogen effluvium usually lasts around three to six months, and it takes several more months for your hair to regain its previous volume because hair grows slowly (4).

You may notice less hair falling out first, followed by new hairs and gradual improvement in thickness.

How to prevent Mounjaro hair loss

You cannot prevent Mounjaro-related hair loss completely, but you can reduce some of the factors that may contribute to it.

Make sure you are eating enough

Because of what Mounjaro does in the body, you may notice you have less appetite and find it easier to eat less. But the aim is not to stop feeling hungry all together or eat as little as possible.

Weight loss does not require severe food restriction. Eating too little may increase the physiological stress associated with losing a lot of weight and make it harder to get enough protein, iron and other nutrients needed for normal hair growth (2,7).

If you have almost no appetite, regularly cannot finish even small meals, are skipping food because nausea or vomiting, or other side effects make eating difficult, speak to your prescriber. Your Mounjaro dose or how quickly you are moving through the dose schedule may need reviewing.

Eat enough protein and iron-rich foods

Getting enough protein on Mounjaro is particularly important. It helps you feel fuller between meals and helps to maintain muscle while you lose fat. Hair is largely made from a protein called keratin, so getting enough protein through your diet also helps support normal hair growth.

Good protein-rich foods you could include in your diet are:

Eggs
Fish
Chicken and other lean meats
Yoghurt and cottage cheese
Beans and lentils
Tofu and other soya foods

Many of these foods can also help with your iron intake, which is also important for normal, healthy hair growth (7). Meat, fish and eggs provide iron, while beans, lentils and some green vegetables provide plant-based iron.

Not every meal or snack needs to be high-protein, but try to include a protein source regularly throughout the day, especially if Mounjaro has made your portions much smaller.

Keep your meals balanced

Alongside protein-rich foods, try to include a mix of fruits, vegetables, wholegrains, and healthy fats. The Eatwell Guide is a useful way to picture this balance across your overall diet (8).

Eating from a range of food groups helps provide nutrients involved in normal hair growth, including iron, zinc and several vitamins. You do not need a “perfect” diet, but keeping some variety in your meals can help reduce the risk of vitamin deficiencies that cause hair loss while you are losing weight.

For more practical meal ideas, see our guide to what to eat on Mounjaro.

Increase your Mounjaro dose gradually

Do not move up through the Mounjaro doses faster in an attempt to lose weight more quickly.

The starting dose for Mounjaro is 2.5mg of Tirzepatide. You then have to increase the Mounjaro dose in 2.5mg steps, but only after you have spent at least four weeks on the current dose (1). Increasing gradually gives your body time to adjust and may make side effects easier to manage.

Moving up too quickly may increase some of the factors linked with hair loss because:

Digestive side effects such as nausea, vomiting and diarrhoea can make it harder to eat enough and maintain good nutrition (1).
Higher doses of Tirzepatide generally produce greater weight loss (5), but faster or greater weight loss is not necessarily better for your hair.

Following the prescribed dose schedule may help avoid unnecessarily rapid changes and side effects that make maintaining good nutrition more difficult (1).

How to stop hair loss on Mounjaro

Hair loss on Mounjaro usually improves gradually without needing a specific hair-loss treatment. When treating telogen effluvium, the main aim is to identify and reduce whatever is triggering the shedding, then give your normal hair cycle time to recover.

If your hair has already started shedding, do not stop Mounjaro without speaking to your prescriber first. Stopping treatment will not necessarily make your hair grow back any faster, and the factors contributing to hair loss can often be addressed without stopping Mounjaro altogether.

Think about whether anything treatment-related could still be contributing, such as:

Very rapid weight loss
Eating much less than usual
Ongoing vomiting or nausea with Mounjaro

If so, adjusting your Mounjaro dose may reduce the trigger. Never change your Mounjaro dose yourself; always ask your prescriber to review your treatment plan, progress, and side effects.

For example, higher doses of Tirzepatide tend to produce greater weight loss (5). If you are losing weight very quickly, your prescriber may decide that a lower dose may be more appropriate. If digestive side effects are making it hard to eat normally and get all the nutrients you need, they may suggest staying at a lower dose or a little longer to make treatment easier to tolerate.

Once the trigger has been reduced, your hair will still need time to recover. Hairs that have already entered the resting phase may continue to fall out for a while, so you may notice the amount of shedding gradually decrease before your hair starts to look thicker again.

In the meantime, be gentle with the hair you have. Avoid very tight hairstyles, harsh brushing, frequent heat styling and chemical treatments where possible, as breakage can make thinning look more noticeable while your hair is recovering.

If shedding continues, gets worse or starts to look different from general thinning, speak to your doctor or pharmacist so they can check whether another cause may be involved.

When to talk to your doctor or pharmacist about Mounjaro & hair loss

Speak to your doctor, pharmacist or Mounjaro prescriber if:

Hair loss continues for more than six months
You develop distinct bald patches rather than general shedding
Your scalp is inflamed, painful, very itchy or scaly
You are struggling to eat enough because of Mounjaro side effects
You are losing weight unusually quickly
You have other symptoms such as marked tiredness, feeling unusually cold or symptoms that could suggest a nutritional deficiency
You are unsure whether Mounjaro is responsible
They may review your symptoms, medicines and medical history, and sometimes arrange blood tests to check for problems such as iron deficiency or thyroid disease.