What to expect in the first month of GLP-1 treatment

Key takeaways

• Starting a glucagon-like peptide-1 (GLP-1) receptor agonist like Wegovy or Ozempic means beginning on the lowest dose to help your body adjust. Side effects like nausea, constipation, or low energy may appear in the first week.
• Over the first month, you may notice decreased appetite, reduced food cravings, and feeling fuller faster as the medication builds in your system. Blood sugar improvements may begin within the first 2 weeks.
• Full effects take time — blood sugar management may stabilize when you reach a maintenance dose, and weight loss can continue for up to a year or longer. Your doctor will likely increase your dose every 4 weeks until the desired effect is reached.

Overview

Starting a glucagon-like peptide-1 (GLP-1) receptor agonist medication like Wegovy or Ozempic is a significant step in your health journey, but it may feel intimidating at first. There are typically a lot of changes to get used to, both in your body and in your day-to-day life.

It’s important to know that GLP-1 treatment isn’t an instant fix, and it may take some time before you see concrete results. With that said, let’s take a look at what you can expect in the first 30 days of starting a GLP-1.

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What to expect in the first week

Week 1 of GLP-1 treatment is less about dramatic changes and more about getting used to a new routine. In the first week, you’ll be on the lowest dose of your medication. If you’ve been prescribed an injectable GLP-1, your doctor may show you or a caregiver how to give the shot at home.

Immediately after prescribing a GLP-1, your doctor should also provide you with some lifestyle recommendations, as GLP-1s are typically only prescribed alongside diet changes and increased exercise. You can use this time to discuss these recommendations and come up with a diet or exercise plan.

In week 1, your body begins to adjust to the new medication. Most people don’t notice many changes in weight or blood sugar at this stage, but you might start to notice the first side effects, such as nausea or vomiting, constipation, bloating, diarrhea, and low energy.

What to expect in the second week

In week 2, the medication is beginning to build up in your system, and you may notice changes in how your body responds to food and hunger. You may notice your appetite is lower, or you might notice fewer cravings. You may also feel fuller faster when eating.

You can also continue to build healthy lifestyle habits in week 2, and you can start to settle into your new routine. Make sure you prioritize hydration and quality rest, alongside slowly increasing your movement and making small switches in your diet.

What to expect in the third week

After 3 weeks of GLP-1 treatment, you’re still at the starting dosage. It may still be several more months of treatment before you see the full benefits of the medication as you go through a process of increasing your dose.

However, you will likely continue to experience changes, such as decreased appetite, feeling fuller for longer, or reduced food cravings. You may notice fewer side effects, especially those affecting the gastrointestinal (GI) tract, as your body gets used to the medication.

At this stage, you may notice mild weight loss, although this is different for everyone — don’t feel disheartened if you don’t see changes on the scale yet.

What to expect in the fourth week

In week 4, the medication should be building to a steady state in your body. You may notice that your body has adjusted to the low dose and you no longer notice side effects.

Effects like reduced food noise, decreased appetite, or other effects may be more noticeable. You may also begin to experience modest weight loss or improvements in blood sugar levels.

You will likely check in with your doctor at this point. Since the first month is a low dose meant just to get your body used to the drug, they will discuss whether to keep you where you are (if you’re experiencing noticeable side effects) or titrate (step up) your dose for month two.

Pro tip for month one: Prioritize protein and water. When your appetite drops sharply, it is easy to accidentally under-eat protein, which can lead to muscle loss. Sip water throughout the day to keep your digestion moving smoothly and ward off dehydration-induced headaches.

Beyond the first month of treatment

Typically, your doctor will increase your dosage every 4 weeks until the desired effect is reached. You may notice GI side effects cropping up each time your dose is increased, but if these are intolerable, you can speak with your doctor about staying at the same dose until your body gets used to it.

Even after one month of treatment, you may still not notice the full effects of your medication. For example, in Ozempic’s clinical trials, participants experienced the drug’s full effects on blood sugar management after 12 weeks.

And with weight loss drugs like Wegovy, you may continue to see weight loss for up to a year or longer. According to some 2025 research, people taking GLP-1s for weight management can lose up to 25% of their body weight in one year of treatment.

Online care for GLP-1s

If a doctor has prescribed a GLP-1, it’s important to take the medication as directed for as long as your doctor recommends. However, some people might face barriers to accessing these drugs, including high costs and access to healthcare appointments.

Online care may make getting treatment easier. With Optum Perks Online Care, for example, you can get a refill of a weight loss prescription or get help with an existing prescription.

With this service, you can submit an online form answering a few questions about your condition, and a licensed healthcare professional will respond soon after — without the need to make an in-person appointment.

Summary

The first 30 days of GLP-1 treatment are not a time of dramatic changes to your weight or blood sugar. Instead, they’re a time for your body to get used to the medication and for the drug to get to work behind the scenes.

In the first 4 weeks, you might notice side effects kicking in, but you may also see mild changes to your appetite and food cravings.

Remember that treatment is a marathon, not a sprint, and it may take some time to see the benefits that are starting to increase behind the scenes.

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