Achieve Your Weight Loss Goals: Understanding How GLP-1 Medications Work in Your System

If you’ve been exploring medical weight loss options, you’ve likely heard about GLP-1s — once-weekly injections that have transformed how we approach long-term weight management. These prescription medications mimic natural hormones in your body to help regulate appetite and blood sugar levels, leading to sustainable weight loss results for many patients.

At De La Belle Wellness & Spa in Memphis, Tennessee, we receive many questions from patients about these treatments, particularly regarding how they work, how long they stay in your system, and why they can make you feel tired. Understanding the effects of GLP-1s is crucial for setting realistic expectations and planning your weight loss journey.

How Do GLP-1 Medications Work?

GLP-1 medications work by mimicking a hormone called glucagon-like peptide-1 (GLP-1), which your intestines naturally release after eating. This hormone sends signals to your brain that you’re full, reducing hunger and helping you consume fewer calories throughout the day.

These medications also slow the rate at which food leaves your stomach, helping you feel satisfied longer. Additionally, they regulate blood sugar by stimulating insulin release when glucose levels are high and reducing glucagon production, which normally triggers the liver to release stored glucose.

The Science of Appetite & Hunger Signals

The relationship between your brain and appetite is far more complex than simply feeling hungry when your stomach is empty. Your brain contains specialized centers that process these signals through an intricate network of neural pathways and hormones.

GLP-1s work directly on these neural pathways, particularly in the hypothalamus, the brain’s hunger control center. When GLP-1s activate receptors in this region, it triggers a cascade of effects that dampen the activity of hunger-promoting signals.

Recent research is also starting to show that GLP-1s also have an effect on reward processing — the same pathways involved in pleasure and addiction. Similar to drugs or alcohol, highly palatable foods activate the brain’s reward system, which can trigger cravings and overeating. GLP-1s reduce the intense pleasure response to these calorie-dense foods.

This dual action — reducing physiological hunger signals while simultaneously diminishing the “reward” associated with eating — helps explain why many patients report not just eating less but actually desiring different types of foods. Many notice a shift in preference toward healthier, less processed options as the medication alters important pathways in the brain.

Duration in Your System: The Half-Life Factor

When discussing how long a medication stays in your system, medical professionals often refer to its “half-life” — the time it takes for half of a drug to be eliminated from your bloodstream. For GLP-1 weight loss medications, this can vary depending on the specific formulation.

The half-life of these medications is about seven days, and it generally takes five half-lives for a medication to be cleared from the body. Based on this, GLP-1 medications stay in your system for about five weeks, but that doesn’t necessarily mean they are effective that entire time. The effects gradually taper off as more of the medication is eliminated, with most people starting to experience food cravings and hunger a week after their last injection. 

At De La Belle Wellness & Spa, our GLP-1 medications are designed for weekly injections, making them a convenient option for patients who prefer less frequent dosing.

Managing GLP-1 Fatigue & Tiredness 

Many patients report experiencing fatigue while taking GLP-1 medications. If you’re one of these patients, you might be wondering why weight loss injections make you feel more tired than usual. This common side effect is related to how these medications work in your body.

The reduction in caloric intake alone can cause your energy levels to dip, especially during the initial adjustment period. Your body needs time to adapt to the decreased food consumption while still meeting energy demands. The medication can also slow gastric emptying, which may affect how quickly your body absorbs nutrients needed for energy production.

Additionally, some patients experience nausea, vomiting and digestive upset, which can contribute to feelings of tiredness. Changes in blood sugar levels, fluid intake and sleep patterns can further exacerbate fatigue symptoms, leaving you feeling drained.

Most patients find that fatigue improves within the first few weeks of starting treatment as they adjust to the medication. Staying properly hydrated, eating a balanced diet and maintaining a regular sleep schedule can all help combat GLP-1 medication-related fatigue. 

Recommended Treatment Timeline

GLP-1 medications may seem like a “magic cure” for obesity, but your results won’t develop overnight, and keeping the weight off requires patience, dedication and a willingness to adopt healthy lifestyle changes. At De La Belle Wellness & Spa, we typically recommend patients stay on GLP-1 medications for at least six to 12 months for the best long-term outcome. 

However, each patient’s treatment plan may vary, depending on factors like:

• Initial weight and health status 
• How well they respond to the medication 
• Whether they experience significant side effects 
• Ability to maintain healthier habits

For some patients, providers may recommend continuing the medication indefinitely to maintain weight loss, particularly for those with obesity-related health conditions that improve with long-term weight management, such as diabetes, sleep apnea or high blood pressure.

Why Timing Matters for Your Treatment

The duration of GLP-1s affects both their efficacy and side effects. Most patients experience the strongest appetite suppression (and nausea, stomach pain or vomiting) the first few days after an injection, with effects tapering slightly before the next scheduled dose. Fortunately, the side effects associated with GLP-1s decrease over time as your body gets used to the medication.

Understanding this pattern can help you plan your meals and social events accordingly. We recommend taking your GLP-1 medication on the same day each week. You can switch it up and change your injection day as long as it has been at least 48 hours since your last dose. 

Start Your Weight Loss Journey Today

Ready to discover if GLP-1 weight loss medications are right for you? At De La Belle Wellness & Spa, our medical team creates personalized treatment plans based on your unique health profile and weight loss goals. We’ll guide you through every step of the process, from your initial consultation to the ongoing support you’ll need to achieve and maintain your results. 

Call our office in Memphis, Tennessee, today at 901-459-3338 to schedule your consultation and learn more about how we help you lose weight and keep it off with GLP-1 medications.