Exclusive: FDA Adds Hair Loss to Zepbound’s Side Effects

Here’s What It Means for You, and What You Can Do

Original posted at obesity.news/ on Sep 29, 2025

Hair loss. It’s the one side effect that rarely shows up in glossy commercials, but it shows up every single day in our community. Women posting photos of clumps of hair in their showers, asking if something is wrong, asking if they’re alone. For women who exepreince this, it can be terrifying, or even treatment altering.

This week, the FDA made it official: alopecia (hair loss) has been added to the label for tirzepatide, sold as Zepbound for obesity and Mounjaro for diabetes. For many of us, this feels less like “new information” and more like long-overdue validation.

A post shared by @manonthemounjaro

Why It Happens

When you lose weight quickly, your body goes into conservation mode. It prioritizes survival. Calories are cut, hormones shift, energy demand changes. And in that brutal triage system, hair is seen as nonessential. Your body will let it go to protect what it views as more important, your heart, your brain, your blood sugar.

The medical term is telogen effluvium, and we see it also after bariatric surgery, crash diets, illness, childbirth, and yes, rapid weight loss on GLP-1s like Zepbound.

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What Patients Report

Here is the good news: within our community, most people describe this hair loss as temporary. It tends to happen in the middle of rapid weight loss, and it usually slows or stops when the weight levels out. And in most cases, hair grows back.

Patients often say things like:

• “Once my weight stabilized, the shedding stopped.”

• “My hair is thinner, but it is slowly coming back.”

• “It was scary at first, but it was temporary.”

Hearing this from real people matters. Because in the moment, it can feel like one massive loss you weren’t prepared for mentally or emotionally. In fact, many are so terrfied by the experience, they may abandon treatment all together.

What You Can Do

There is no magic pill to stop shedding, but there are steps that may help:

• Protein first. In times of calorie restriction, your body needs adequate protein to protect hair and muscle. Skimping on protein makes shedding worse.

• Balanced nutrition. Iron, zinc, and vitamins all play a role in hair growth. Deficiencies can turn normal shedding into something more severe. We did a full article on this here.

• Patience. Most shedding slows when your body adjusts and stabilizes at its new weight.

It’s not about perfection. It’s about giving your body enough resources to keep what it doesn’t think it needs.

Let’s Talk About It

If you have experienced hair loss on Zepbound, what helped you? Did protein make a difference? Did supplements? Did it resolve on its own?

And for those of you whose experience looked different, maybe the shedding didn’t stop, or maybe you found a trick nobody talks about, please share it below! Because the FDA can put “alopecia” on a label, but only patients can teach other patients what it feels like and how to get through it.

Why This Update Matters

Adding hair loss to the official label means one important thing: you are not imagining it. This side effect is real. The system is finally acknowledging what patients have been saying for years.

It also means more honest conversations between patients and doctors. No more being dismissed when you bring it up. No more feeling like you are the only one.

Stay tuned to OnThePen.com for more updates and in-depth analysis on the latest developments in weight loss and diabetes treatments. Sharing this article is a powerful form of advocacy that brings us closer to our goal of educating the masses and reducing the stigma of obesity. If you found this article insightful, please share it within your networks, especially in Facebook groups and Reddit forums dedicated to GLP-1 medications and diabetes management. Together, we can make a difference.