Wegovy for weight loss
Overview
As a nutrition support pharmacist, you’re likely hearing a lot about Wegovy as an option for weight loss. This injectable semaglutide, a GLP-1 agonist, works similarly to Ozempic (injectable) and Rybelsus (oral) — both widely used for managing type 2 diabetes. For more insights, check out our detailed discussion: "Weight Loss Medications Don't Always Work".
Wegovy and weight loss
Dosage and weight loss efficacy
Wegovy starts at the same initial dose of 0.25 mg weekly as Ozempic, but gradually increases to a target dose of 2.4 mg weekly (see table 1). In contrast, Ozempic has a maximum dose of 1 mg weekly. When used at 2.4 mg weekly for a year, Wegovy can achieve around 10% to 12% greater weight loss compared to placebo—translating to approximately 9 kg (20 lb) for a 90 kg (200 lb) patient. This efficacy is nearly double the weight loss achieved with daily Saxenda (liraglutide), another GLP-1 agonist used for obesity, and is comparable to Qsymia (phentermine/topiramate ER). Other prescribed weight loss medications tend to yield less significant results.
| Table (1). Wegovy™ Dosing Schedule | |||
|---|---|---|---|
| Initiate and adjust dose using the following schedule: In patients who do not tolerate a dosage increase, consider delaying the increase for an additional 4 weeks... | |||
| Semaglutide (Wegovy, U.S. only) |
Week 1 through week 4: 0.25 mg once weekly. | Note: For use as an adjunct to diet and exercise in patients with a BMI ≥ 30, or in patients with a BMI ≥ 27 and ≥ 1 weight-associated comorbidity (e.g., hypertension, dyslipidemia). | Discontinuation rate due to adverse effects: one out of every 28 patients. |
| Week 5 through week 8: 0.5 mg once weekly. | |||
| Week 9 through week 12: 1 mg once weekly. | |||
| Week 13 through week 16: 1.7 mg once weekly. | |||
| Week 17 and thereafter (maintenance dosage): 2.4 mg once weekly; if not tolerated, may temporarily decrease dosage to 1.7 mg once weekly for up to 4 additional weeks, then increase to 2.4 mg once weekly. | |||
| Missed dose: Missed dose should be administered as soon as possible within 5 days; resume usual schedule thereafter. If > 5 days have elapsed, skip the missed dose and resume administration at the next scheduled weekly dose. If more than 2 consecutive doses are missed, resume dosing as scheduled; alternatively, may reinitiate dosage adjustment schedule. | |||
Educate patients that gastrointestinal (GI) side effects are common with Wegovy. However, most patients can tolerate these effects if the dose is titrated gradually over a 16-week period. It’s important to weigh these side effects against the potential downsides of other weight loss medications. For instance, Qsymia may carry a risk of kidney stones due to its topiramate content. Additionally, consider the cost implications, as both Wegovy and Saxenda can be expensive for patients.
Lifestyle changes and BMI guidelines
Continue to emphasize the importance of lifestyle changes before initiating weight loss medications. Consider referring patients for bariatric surgery if their body mass index (BMI) is 35 or higher. Avoid discussing pharmacotherapy unless patients present with a BMI of 30 or above, or a BMI of 27 or higher accompanied by a weight-related condition, such as diabetes.
We prefer treatment with Wegovy (semaglutide) rather than Saxenda (liraglutide); administration of Wegovy is once weekly rather than once daily, and Wegovy has greater efficacy for weight loss than Saxenda.
When to use and when to stop Wegovy
Consider using Wegovy when a GLP-1 agonist is preferred for weight loss, though note that it is currently unavailable in Egypt. Discontinue the medication if patients cannot tolerate the 2.4 mg/week dose or if they fail to achieve at least a 5% reduction in body weight after 12 weeks at this dosage. For patients who respond well, long-term use may be beneficial. Avoid combining Wegovy with other weight loss medications, as evidence for combined use is lacking. Additionally, refrain from using Wegovy alongside other GLP-1 agonists or DPP-4 inhibitors (such as Januvia) due to their similar mechanisms of action.
References
- Wadden TA, Bailey TS, Billings LK, et al. Effect of Subcutaneous Semaglutide vs Placebo as an Adjunct to Intensive Behavioral Therapy on Body Weight in Adults With Overweight or Obesity: The STEP 3 Randomized Clinical Trial. JAMA. 2021 Apr 13;325(14):1403-1413.
- Rubino D, Abrahamsson N, Davies M, Hesse D, et al. Effect of Continued Weekly Subcutaneous Semaglutide vs Placebo on Weight Loss Maintenance in Adults With Overweight or Obesity: The STEP 4 Randomized Clinical Trial. JAMA. 2021 Apr 13;325(14):1414-1425.
- Wilding JPH, Batterham RL, Calanna S, Davies M, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. N Engl J Med. 2021 Mar 18;384(11):989.