Zepbound (tirzepatide) is a prescription drug that’s used for weight loss in certain adults. Zepbound comes as a liquid solution inside prefilled injection pens. You’ll inject the drug under your skin once per week.

Zepbound basics

Zepbound is a brand-name medication. It contains the active ingredient tirzepatide. (An active ingredient is what makes a drug work.) There currently isn’t a generic version of the drug.

Zepbound is prescribed for weight loss and long-term weight management in adults with either:

Zepbound is prescribed along with a reduced-calorie diet and increased exercise.

Zepbound helps you lose weight by reducing your appetite. The drug also slows down digestion, so after eating you feel fuller sooner and for longer. These effects help you consume fewer calories, which can help with weight loss and long-term weight management.

It’s important to note that your doctor will likely not prescribe Zepbound if you:

* An active ingredient is what makes a drug work.

Like most drugs, Zepbound may cause mild or serious side effects. The lists below describe some of the more common side effects that Zepbound may cause. These lists don’t include all possible side effects.

Keep in mind that side effects of a drug can depend on:

  • your age
  • other health conditions you have
  • other medications you take
  • your dosage

Your doctor or pharmacist can tell you more about the potential side effects of Zepbound. They can also suggest ways to help reduce side effects.

Mild side effects

Here’s a list of some of the mild side effects that Zepbound can cause. To learn about other mild side effects, talk with your doctor or pharmacist or read Zepbound’s prescribing information.

Mild side effects of Zepbound that have been reported include:

Mild side effects of many drugs may go away within a few days to a couple of weeks. But if they become bothersome, talk with your doctor or pharmacist.

* To learn more about this side effect, see the “Allergic reaction” section below.

Serious side effects

Serious side effects from Zepbound can occur, but they aren’t common. If you have serious side effects during your Zepbound treatment, call your doctor right away. But if you think you’re having a medical emergency, you should call 911 or your local emergency number.

Serious side effects of Zepbound that have been reported include:

* For more information, see the “What should be considered before starting Zepbound?” section below.
† To learn more about this side effect, see the “Allergic reaction” section below.
This side effect was not reported in studies of Zepbound, but it occurred in studies of weight loss drugs similar to Zepbound.

Allergic reaction

Some people may have an allergic reaction to Zepbound.

Symptoms of a mild allergic reaction can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)

A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include swelling under your skin, usually in your eyelids, lips, hands, or feet. They can also include swelling of your tongue, mouth, or throat, which can cause difficulty breathing.

Call your doctor right away if you have an allergic reaction to Zepbound. But if you think you’re having a medical emergency, call 911 or your local emergency number.

Your doctor will recommend the dosage of Zepbound that’s right for you. Below are commonly prescribed dosages, but always follow the dosage your doctor prescribes.

Form and strengths

Zepbound comes as a liquid solution in prefilled, single-dose, disposable injection pens. The drug is given as an injection under your skin. Zepbound is available in six strengths:

  • 2.5 milligrams in 0.5 milliliters of liquid solution (2.5 mg/0.5 mL)
  • 5 mg/0.5 mL
  • 7.5 mg/0.5 mL
  • 10 mg/0.5 mL
  • 12.5 mg/0.5 mL
  • 15 mg/0.5 mL

Recommended dosage

The recommended starting dosage is 2.5 mg injected once per week for 4 weeks. This low dose helps your body get used to the medication. It also reduces your risk of having digestive side effects, such as nausea and diarrhea.

After the first 4 weeks, your doctor will increase your dosage to 5 mg injected once per week for 4 weeks.

If needed, your doctor may increase your weekly dose in increments of 2.5 mg until you reach the dosage that’s right for you. You’ll inject each prescribed dose for at least 4 weeks before your doctor increases your dose again.

The maximum dosage of Zepbound is 15 mg injected once per week.

How to inject

Your doctor will explain how you should inject Zepbound. They’ll also explain how much to inject and how often. Be sure to follow your doctor’s instructions.

Zepbound is available as a liquid solution that’s given as an injection under your skin. Your doctor or another healthcare professional will show you how to give yourself these injections at home. You’ll also find instructions in the leaflet that comes with the medication.

You can also visit the manufacturer’s website for more instructions, including a video on how to inject Zepbound.

Injection sites

You should inject Zepbound into your stomach, thigh, or the back of your upper arm. (If you want to have the injections in your upper arm, another person will need to administer the injections for you.)

The injection should be given into a slightly different spot each week to avoid irritating your skin.

Questions about Zepbound

Below are some common questions about Zepbound.

  • Should I inject Zepbound with food? You can inject Zepbound with or without food.
  • Is there a best time of day to inject Zepbound? Zepbound is injected once per week. You can inject Zepbound at any time of day, but it’s best to inject a dose on the same day each week.
  • What if I miss a dose of Zepbound? If you miss a dose of Zepbound, inject it as soon as you remember. But if it’s been more than 4 days (96 hours) since your dose was due, skip the missed dose and inject your next dose at the usual time. You should not inject two doses at once to make up for a missed dose. And do not inject two doses within 3 days (72 hours) of each other. Doing so could raise your risk of side effects.
  • Will I need Zepbound treatment long term? If Zepbound works for you and doesn’t cause bothersome side effects, your doctor will likely recommend long-term treatment with it.
  • How long does Zepbound take to work? Zepbound starts working as soon as you start treatment, but it might take a few weeks before you begin to lose weight. Weight loss will also depend on your calorie intake and level of physical activity. If you have questions about what to expect with Zepbound, talk with your doctor.


Do not inject more Zepbound than your doctor prescribes. Injecting more than this can lead to harmful effects.

What to do in case you inject too much Zepbound

Call your doctor if you think you’ve injected too much Zepbound. You can also call 800-222-1222 to reach America’s Poison Centers or use its online resource. But if you have severe symptoms, immediately call 911 or your local emergency number. Or go to the nearest emergency room.

Below is important information you should consider before starting Zepbound.


Taking a drug with certain medications, vaccines, foods, and other things can affect how the drug works. These effects are called interactions.

Before starting Zepbound treatment, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also, tell them about any vitamins, herbs, and supplements you take. Sharing this information can help you avoid potential interactions.

If you have questions about drug interactions that may affect you, talk with your doctor or pharmacist.

Zepbound can interact with several other medications. It can also interact with certain supplements as well as certain foods.

Drug interactions

Zepbound slows down digestion, so it could affect the way other drugs are absorbed into your body.

Below is a list of medications that can interact with Zepbound. This list does not contain all drugs that may interact with Zepbound.

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

Drug group or drug nameDrug examples
birth control pills• ethinyl estradiol/norethindrone (Junel, others)
• ethinyl estradiol/drospirenone (Yaz, others)
insulins• insulin lispro (Humalog, others)
• insulin glargine (Lantus, others)
sulfonylureas• glipizide (Glucotrol XL)
• glimepiride (Amaryl)
warfarin (Jantoven)

Zepbound and alcohol

Alcohol is not known to interact with Zepbound. It should be safe to consume alcohol during your Zepbound treatment.

If you have questions about how much alcohol may be safe to consume with Zepbound, talk with your doctor or pharmacist.

Pregnancy and breastfeeding

Zepbound is not recommended during pregnancy. Weight loss during pregnancy may cause fetal harm.

If you become pregnant during Zepbound treatment, you should stop treatment and contact your doctor. You’re also encouraged to join the pregnancy registry for Zepbound. Pregnancy registries gather information about the safety of a drug during pregnancy. For more information, call 800-545-5979 or talk with your doctor.

It’s not known whether it’s safe to inject Zepbound while breastfeeding.

If you’re pregnant or breastfeeding, or planning to become pregnant or to breastfeed, talk with your doctor before starting Zepbound treatment.

Birth control

If you’re able to become pregnant, your doctor may recommend using a form of birth control during Zepbound treatment.

However, Zepbound can make birth control pills less effective. Your doctor will likely recommend using a different or additional form of birth control for the first 4 weeks of Zepbound treatment and for 4 weeks after any dose increases.

Boxed warning

Zepbound has a boxed warning about a possible risk of thyroid cancer. A boxed warning is the most serious warning from the Food and Drug Administration (FDA).

The active ingredient* in Zepbound, tirzepatide, can cause thyroid tumors in animals. It’s not known whether the drug can cause thyroid cancer in humans. But due to the possible risk, your doctor will likely not prescribe Zepbound if:

During your Zepbound treatment, contact your doctor if you develop symptoms of thyroid cancer. These may include:

  • hoarseness that doesn’t get better
  • a lump in your neck
  • difficulty swallowing
  • difficulty breathing

If you have questions or concerns about this warning, talk with your doctor.

* An active ingredient is what makes a drug work.

Other warnings

Zepbound can sometimes cause harmful effects in people who have certain conditions. This is known as a drug-condition interaction. Other factors may also affect whether Zepbound is a good treatment option for you.

Talk with your doctor about your health history before you start Zepbound. Be sure to tell them if any of the following factors apply to you:

Help is out there

If you or someone you know is in crisis and considering suicide or self-harm, please seek support:

If you’re calling on behalf of someone else, stay with them until help arrives. You may remove weapons or substances that can cause harm if you can do so safely.

If you are not in the same household, stay on the phone with them until help arrives.

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Find answers to some commonly asked questions about Zepbound.

How does Zepbound compare with Mounjaro?

Zepbound and Mounjaro are both prescribed for weight loss. But the Food and Drug Administration (FDA) has only approved Zepbound for this use.

Mounjaro is approved by the FDA for improving blood sugar levels in people with type 2 diabetes. But it’s sometimes prescribed off-label for weight loss. (With off-label use, doctors prescribe a drug for a purpose other than what it’s approved for.)

Zepbound and Mounjaro contain the same active ingredient,* tirzepatide. Because of this, the drugs have similar side effects.

Zepbound and Mounjaro both come as prefilled, single-dose injection pens. They’re both given once per week as an injection under your skin.

If you have other questions about how Zepbound and Mounjaro compare, talk with your doctor. They can help you find the best treatment option for you.

* An active ingredient is what makes a drug work.

Is Zepbound safe for older adults?

Yes, Zepbound is usually safe for older adults (people ages 65 years and over). In studies, side effects of Zepbound were similar in older and younger adults.

However, older adults may be more likely to take other medications that could interact with Zepbound. Older adults are also more likely to have health conditions, such as kidney problems, which may make Zepbound unsafe for them.

If you have questions about Zepbound’s safety based on your age, talk with your doctor.

Does Zepbound cause long-term side effects?

It’s unlikely. Long-term side effects weren’t reported in studies of Zepbound.

If you’re concerned about possible long-term side effects from Zepbound, talk with your doctor or pharmacist.

Whether you have health insurance or not, cost may be a factor when you’re considering Zepbound. What you’ll pay for Zepbound may depend on several things, such as your treatment plan and the pharmacy you use.

Here are a few things to consider regarding cost:

  • Generic form. Zepbound is not currently available as a generic drug. Generics usually cost less than brand-name drugs.
  • Savings card. If you have questions about how to pay for your prescription, talk with your doctor or pharmacist. A savings card may also be available.

You can also check out this article to learn more about saving money on prescriptions.

Other drugs are available that can help weight loss. If you’d like to explore an alternative to Zepbound, talk with your doctor. They can tell you about other medications that might work well for you.

The following drugs are alternatives to Zepbound:

  • semaglutide (Ozempic, Wegovy)
  • liraglutide (Saxenda, Victoza)
  • tirzepatide (Mounjaro)
  • orlistat (Alli, Xenical)
  • phentermine (Adipex-P, Lomaira)
  • phentermine and topiramate (Qsymia)
  • bupropion and naltrexone (Contrave)

If you have questions about Zepbound, talk with your doctor or pharmacist. Questions you may want to ask include:

  • What diet and exercise plan should I follow during treatment with Zepbound?
  • How long will I need to have Zepbound treatment?
  • Will I gain weight again after stopping Zepbound treatment?
  • How does Zepbound compare with other weight loss drugs?

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Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.