What to know about Zepbound, the new weight loss drug
An estimated 70% of American adults are overweight or obese, and many of these people have other weight-related conditions. Losing just 5% to 10% of body weight through diet and exercise has been associated with a reduced risk of heart disease in adults who are overweight or obese. A new obesity drug that has shown incredible results in clinical trials has just been approved and should hit the market by the end of the year. It is now likely the most effective treatment to combat obesity besides bariatric surgery.
The US Food and Drug Administration (FDA) approved drugmaker Eli Lilly’s weight-loss medication Zepbound on November 8, 2023, to treat chronic obesity. It contains the same active ingredient, tirzepatide, as the type 2 diabetes drug Mounjaro. Tirzepatide joins a similar drug called semaglutide that was first developed by Novo Nordisk to treat type 2 diabetes under the brand name Ozempic and has since been approved as an obesity treatment under the brand name Wegovy.
With the approval of Zepbound, this may help ease some of the shortages that have plagued Mounjaro, Ozempic, and Wegovy over the last year. So how does Zepbound work, what are its side effects, and is it better than these other medications for weight loss? Keep reading to find out.
Zepbound FAQs
Who can use Zepbound?
Zepbound (tirzepatide) is FDA-approved along with a reduced-calorie diet and increased physical activity for chronic weight management in adults with an initial body mass index (BMI) of:
- 30 kg/m² or higher (considered obese)
- 27 kg/m² or higher (considered overweight) with at least one weight-related condition such as high blood pressure, high cholesterol, type 2 diabetes, obstructive sleep apnea, or heart disease
How does Zepbound work?
Tirzepatide, the active ingredient in Zepbound, is a glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptor agonist. It works by mimicking GLP-1 and GIP, hormones naturally produced in your body, which are involved in the regulation of blood sugar and body weight.
GLP-1 targets receptors in your brain to decrease appetite, and it slows down digestion to help you feel full faster and longer. This can help you eat less and lose weight. GLP-1 also stimulates your pancreas to release insulin, which reduces your blood sugar levels. GIP is thought to have similar effects on your body as GLP-1.
What are the side effects of Zepbound?
The most common side effects of Zepbound in clinical trials when compared to placebo include:
- Nausea
- Diarrhea
- Vomiting
- Upset stomach
- Constipation
- Stomach pain
- Hair loss
- Injection site reactions
- Burping
- Fatigue
Zepbound may also cause more serious side effects, including:
- Serious allergic reactions, including:
- Hives
- Swelling of your throat and tongue
- Trouble breathing
- Increased risk of thyroid cancer or thyroid C-cell tumors
- Pancreatitis (inflammation of your pancreas)
- Kidney damage including kidney failure
- Gallbladder problems including gallstones
- Severely low blood sugar (hypoglycemia)
- Vision changes in people with type 2 diabetes
- Worsening depression or thoughts of suicide
Seek immediate medical attention if you notice a lump on your neck, have trouble breathing or swallowing, or have hoarseness that does not go away. Call your healthcare provider immediately if you develop severe pain in your stomach area that may spread into your back, with or without vomiting. Be sure to drink plenty of fluids if you are experiencing stomach-related side effects such as vomiting and diarrhea. Contact your healthcare provider right away if you experience severe pain in the upper part of your stomach, fever, nausea, or vomiting. If you are taking Zepbound along with sulfonylureas or insulins, you may need to adjust the dose of these medications to help avoid low blood sugar levels. Seek medical attention right away if you still feel shaky, dizzy, nervous, irritated, confused, or weak after you have treated yourself for low blood sugar. Notify your healthcare provider if you notice any changes in your vision while taking Zepbound. Contact your healthcare provider immediately or seek medical help if you have worsening depression or thoughts of hurting yourself.
Who should not use Zepbound?
The FDA advises that people with a personal or family history of medullary thyroid cancer or Multiple Endocrine Neoplasia syndrome type 2 should not use Zepbound. You should also avoid this medication if you are allergic to tirzepatide or any inactive ingredient in the product.
How much weight can you lose with Zepbound?
In one clinical trial, people taking 15 mg of tirzepatide, the highest dose, had an average weight loss of 22.5% of their body weight (52 pounds).
At lower doses, average weight loss was:
- 10 mg: 21.4% (48 pounds)
- 5 mg: 16% (35 pounds)
What is the cost of Zepbound?
Lilly announced the list price for a month’s supply of Zepbound to be around $1,060. While it is cheaper than Wegovy (around $1,300 per month), both medications may be expensive depending on your insurance coverage. Contact your insurance company to see if Zepbound is covered and what your copay will be.
Are Mounjaro and Zepbound the same?
Zepbound and Mounjaro contain the same active ingredient, tirzepatide, and are both given as subcutaneous injections once a week, up to 15 mg. The only difference is the approved use: Zepbound for weight loss and Mounjaro for type 2 diabetes.
Related Medications
- Mounjaro (tirzepatide)
- Ozempic (semaglutide)
- Rybelsus (semaglutide)
- Trulicity (dulaglutide)
- Victoza (liraglutide)
- Saxenda (liraglutide)