Can Ozempic, Wegovy, or Mounjaro Cause Hair Loss?

Before analysing whether medications such as Ozempic, Wegovy, or Mounjaro can cause hair loss, it is important to understand that hair loss is a multifactorial process in which various metabolic, hormonal, and nutritional factors play a role.

In recent years, the use of GLP-1 receptor agonists has increased significantly, both in Spain and Mexico, primarily in the treatment of type 2 diabetes and obesity. This rise has made it possible to observe not only their benefits, but also the emergence of new questions from patients.

In clinical practice, it is becoming increasingly common for patients undergoing treatment for weight loss or diabetes to report hair loss or a reduction in hair density associated with these medications. In many cases, the main concern is whether these drugs are directly causing the hair loss, or whether the process is reversible.

Table of Contents

1. What are GLP-1 agonists?
2. Is there a link with hair loss?
3. Telogen effluvium and weight loss
4. Nutritional deficiencies
5. Underlying androgenetic alopecia
6. Metabolic factors
7. Is hair loss reversible?
8. What to do if hair loss occurs
9. Hair assessment
10. Scientific evidence
11. Frequently asked questions

1.What are GLP-1 agonists?

GLP-1 receptor agonists are medications used in the treatment of diabetes and, more recently, in the management of obesity.

The most well-known include:

• Semaglutide (Ozempic, Wegovy)
• Tirzepatide (Mounjaro)

Their use has expanded significantly in recent years due to their effectiveness in blood sugar control, weight loss, and the improvement of metabolic parameters.

2.Is there a link with hair loss?

In clinical practice, it is increasingly common for patients on these medications to report greater hair loss. However, to date, a direct cause-and-effect relationship cannot be confirmed, although a clinical association has been observed in certain patients.

In most cases, hair loss appears to be related to indirect factors associated with the treatment, rather than a direct effect of the drug on the hair follicle.

3.Telogen Effluvium and Weight Loss

One of the most common mechanisms is telogen effluvium. Rapid weight loss can disrupt the hair growth cycle, causing a greater number of follicles to enter the resting phase simultaneously. This results in diffuse hair shedding that typically appears weeks or months after the metabolic change.

This is a process we frequently see in clinical practice, regardless of the cause of the weight loss.

4.Nutritional Deficiencies

During treatment, changes in food intake or nutrient absorption may occur.

Deficiencies in iron, protein, or certain vitamins can affect the hair cycle and promote shedding. For this reason, it is important to assess these factors as part of the overall patient evaluation.

5.Underlying Androgenetic Alopecia

In some cases, hair loss is not a new phenomenon, but rather the manifestation of pre-existing androgenetic alopecia. A reduction in hair density makes follicle miniaturisation more visible — a progressive process that can go unnoticed in its early stages.

This is something we frequently observe in patients both in Madrid and Mexico City, where we regularly carry out hair assessments for this type of case.

6.Metabolic Factors

Some hypotheses suggest that these medications could influence insulin sensitivity or microcirculation. Their direct impact on the hair follicle has not yet been clearly defined, but this forms part of current lines of research.

7.Is Hair Loss Reversible?

When the primary cause is telogen effluvium, hair loss is usually temporary and reversible. However, it is important to obtain an accurate diagnosis, as not all types of hair loss follow the same course or require the same management.

8.What to Do If Hair Loss Occurs

If you notice greater than usual hair loss during treatment, the recommended steps are:

• discuss it with your doctor
• assess possible nutritional deficiencies
• review personal or family history of alopecia
• monitor how the condition evolves over time

It is important not to discontinue treatment without a prior medical assessment.

9.Hair Assessment

Hair loss requires an individualised approach. The clinical assessment includes:

• medical history
• scalp examination
• density and hair calibre analysis

This type of assessment makes it possible to accurately identify the cause of hair loss and propose an individualised therapeutic approach. It is also key to correctly differentiating the origin of the condition and avoiding unnecessary or ineffective treatments.

At our hair clinic in Madrid and Mexico City, we regularly carry out this type of assessment in patients presenting with hair loss associated with metabolic changes or medical treatments. These consultations are becoming increasingly common among patients who experience hair shedding following weight loss.

10.Scientific Evidence

The possible link between GLP-1 agonists and hair loss is an evolving area of research. Current studies describe a clinical association, but do not allow a direct causal relationship to be established.

It is therefore necessary to continue research in this area and to analyse each case on an individual basis.

11.Frequently Asked Questions

Does Ozempic cause hair loss?
No direct relationship has been established, although some patients may notice increased hair shedding during treatment.

Is hair loss permanent?
In most cases, no. It tends to be reversible when caused by telogen effluvium.

Should I stop treatment?
Not without a prior medical assessment.

Can it worsen pre-existing alopecia?
It may make it more visible, particularly in cases of androgenetic alopecia.

Final Note

Hair loss in patients being treated with Ozempic, Wegovy, or Mounjaro is usually related to indirect factors, such as weight loss or nutritional changes.

A proper assessment makes it possible to identify the cause, establish a prognosis, and guide management on an individual basis. In many cases, hair loss in this context is reversible when the underlying cause is correctly identified.

This content has been prepared by the medical team at the Instituto Médico del Prado and reviewed by Dr. Bonilla Juárez and Dr. Muñoz Ramírez.

If you have noticed changes in your hair during treatment, a proper assessment can help you understand what is happening and what options are available to you.

We see patients in both Madrid and Mexico City, tailoring each treatment to the individual characteristics of each patient.

The Instituto Médico del Prado is a clinic specialising in the diagnosis and treatment of hair and scalp conditions. To book an appointment, please contact us through our website or usual communication channels.

References

1. Rojas Lopez RF, Barrera DL, Amaya Muñoz MC, Saavedra Diaz MP. Alopecia as an emerging adverse effect associated with glucagon-like peptide-1 (GLP-1) receptor agonists for weight loss: a scoping review. Cureus. 2025;17(8):e90021. doi:10.7759/cureus.90021.
2. Alsuwailem OA, Alanazi R, Almutairi HM, Asiree RH, Almutairi W, Almutairi TM, et al. Hair loss associated with glucagon-like peptide-1 (GLP-1) receptor agonist use: a systematic review. Cureus. 2025;17(9):e92454. doi:10.7759/cureus.92454.
3. Burke O, Sa B, Cespedes DA, Sechi A, Tosti A. Glucagon-like peptide-1 receptor agonist medications and hair loss: a retrospective cohort study. J Am Acad Dermatol. 2025;92(5):1141-1143. doi:10.1016/j.jaad.2025.01.046.