How long does it take for Ozempic to work?

Key Points

• Your blood glucose (sugar) levels should start to fully decline within the first week after you start using Ozempic (semaglutide) at your regular maintenance dose.
• However, the full effect can take 8 weeks or longer, as this is a long-acting medication that is injected only once per week. You will start with lower doses for the first 4 weeks of treatment to help lower side effects, but this is not an effective dose to lower blood sugar over the long-term.
• Ozempic is administered once weekly, on the same day each week, and can be taken at any time of the day with or without meals
• Your results may be different from other patients, so check with your doctor if you have a concern about your blood sugar levels.

Most patients will start Ozempic treatment at the lower 0.25 mg dose injected once a week for 4 weeks. The 0.25 mg dose is not used as your final maintenance dose to lower your blood sugar. Starting with the lower dose initially may help you tolerate some of the side effects.

After 4 weeks at the 0.25 mg dose, your dose will usually be increased to 0.5 mg per week, then possibly to 1 mg per week, based on your response to treatment and how well you tolerated it

The manufacturer notes that it takes 4 to 5 weeks of once-weekly administration with Ozempic to reach steady state. Steady state is the time during which the concentration of the drug in the body stays consistent. In other words, steady state is when the rate of the drug going into your body is equal to the rate of drug elimination.

Although steady state levels are reached in 4 to 5 weeks, clinical effectiveness with Ozempic will vary from person to person and may take longer due to unique factors such as age, weight, amount of body fluid, additional medications you take, kidney or liver function, or your other medical conditions.

It may also take longer based on how quickly you can achieve your final maintenance dose. Your doctor knows your medical condition the best and can give you specific information on your overall response time to Ozempic.

Type 2 diabetes is long-term (chronic) disease and medications are used for maintenance treatment. The full beneficial effects of Ozempic on your heart require you to take your medication on a long-term basis. Your doctor may combine Ozempic with other diabetes medication to further reduce your blood sugar levels or for added benefits.

Do not stop taking your medication or adjust any doses without speaking to your doctor first.

What side effects are most likely with Ozempic?

The most common side effects reported in ≥5% of patients treated with Ozempic are:

• nausea (16% to 20%)
• vomiting (5% to 9%)
• diarrhea (8% to 9%)
• abdominal (stomach) pain (6% to 7%)
• constipation (3% to 5%)

Stomach side effects are most common when starting treatment but decrease over time in most patients.

In Sept. 2023, the FDA updated the side effects in the label for Ozempic (semaglutide) to emphasize that an ileus, an intestinal blockage, has been reported as a possible side effect. Because this side effect was voluntarily reported, the FDA cannot reliably determine how often this side effect occurs or if the drug actually caused the side effect. Speak to your doctor about your risk for this side effect.

This side effect has also been reported for the other semaglutide products Wegovy and Rybelsus, as well as tirzepatide, the GLP-1/GIP agent approved for type 2 diabetes treatment (Mounjaro) or weight loss (Zepbound).

Related Questions

• What are 4 key Ozempic side effects to watch out for?
• Mounjaro vs Ozempic: How do they compare?
• How do Ozempic, Mounjaro, Wegovy, Zepbound compare for weight loss?

Why am I using Ozempic?

Ozempic (semaglutide) is medication used alongside diet and exercise to improve blood sugar control in adults with type 2 diabetes. Ozempic is not used to treat type 1 diabetes or diabetic ketoacidosis. You doctor may prescribe Ozempic to be used in addition to other diabetes medications, such as metformin or insulin.

Ozempic is also approved to reduce the risk of major cardiovascular (heart and blood vessel) events such as heart attack, stroke, or death in adults with type 2 diabetes and known heart disease.

How does Ozempic help me?

• Ozempic is in a class of drugs known as glucagon-like peptide-1 (GLP-1) agonists (incretin mimetics).
• Ozempic works by binding to GLP-1 receptors and stimulates insulin release from the pancreas when you need it. It helps to lower your blood sugar levels and A1C.
• It also helps to reduce the amount of sugar released by your liver and slows down food leaving your stomach to help prevent blood sugar spikes. It can reduce your appetite and you may lose weight, as well, although Ozempic is not approved for weight loss.
• Ozempic can help to protect you from a heart attack or stroke if you have type 2 diabetes and known heart disease.

How does Ozempic affect my blood sugar?

In clinical studies conducted by the manufacturer, Ozempic was studied as a single treatment compared to placebo (an inactive agent) as well as when combined with other type 2 diabetes medications such as metformin, metformin plus a sulfonylureas, and metformin plus thiazolidinediones.

The effectiveness of Ozempic was compared to sitagliptin, exenatide extended-release, and insulin glargine. Ozempic 0.5 mg and 1 mg injected weekly significantly reduced the A1C levels in all studies ranging from 30 weeks to 56 weeks.

However, reducing your A1C below 7 may take at least 8 weeks, depending upon where your hemoglobin A1C (HbA1C) is when you start Ozempic. In a 56-week study comparing semaglutide to sitagliptin, Ozempic lowered the mean baseline A1C of 8% down to 7% by week 8 of the study. A1C levels were at or below 6.5% by week 16.

In another clinical study, Ozempic monotherapy lowered the A1C by 1.4% to 1.6% after 30 weeks of treatment. It also reduced fasting blood sugar levels by 41 to 44 mg/dL after 30 weeks. The percent of patients achieving an A1C of less than 7% was 70% to 73% of patients using Ozempic compared to 28% of patients using a placebo.

Bottom Line

Your blood sugar levels should start to fully decline within the first week after you start using Ozempic (semaglutide) at your regular maintenance dose. However, the full effects can take 8 weeks or longer, as this is a long-acting medication that is injected only once per week.

You will start with lower doses for the first 4 weeks to help lower side effects, but this is not an effective dose to lower blood sugar over the long-term.

This is not all the information you need to know about Ozempic for safe and effective use. Review the full Ozempic information here, and discuss this information with your doctor or other health care provider.