What are the indications, dosing regimen, contraindications, and monitoring recommendations for Wegovy (semaglutide) in adult weight management?

Wegovy (Semaglutide 2.4 mg) for Weight Management

Wegovy is indicated for chronic weight management in adults with BMI ≥30 kg/m² or BMI ≥27 kg/m² with at least one weight-related comorbidity, and for reducing major adverse cardiovascular events in adults with established CVD and obesity/overweight, always combined with reduced-calorie diet and increased physical activity. 1

FDA-Approved Indications

Wegovy (semaglutide 2.4 mg subcutaneous) has two primary indications 1:

• Cardiovascular risk reduction: To reduce risk of CV death, non-fatal MI, or non-fatal stroke in adults with established CVD and either obesity or overweight
• Weight management: To reduce excess body weight and maintain long-term weight reduction in:
  • Adults and pediatric patients ≥12 years with obesity (BMI ≥30 kg/m²)
  • Adults with overweight (BMI ≥27 kg/m²) with at least one weight-related comorbidity (hypertension, dyslipidemia, type 2 diabetes, obstructive sleep apnea)

The AGA 2022 guidelines conditionally recommend semaglutide 2.4 mg as a preferred agent, noting it "may be prioritized over other approved AOMs for long-term treatment of obesity for most patients" given the magnitude of net benefit 2.

Dosing Regimen

Start at 0.25 mg weekly and escalate monthly to minimize gastrointestinal adverse effects 2, 1:

Week	Dose
1-4	0.25 mg once weekly
5-8	0.5 mg once weekly
9-12	1.0 mg once weekly
13-16	1.7 mg once weekly
17+	2.4 mg once weekly (maintenance) or 1.7 mg if not tolerated

Administration details 1:

• Inject subcutaneously in abdomen, thigh, or upper arm
• Same day each week, any time of day, with or without meals
• If dose escalation not tolerated, delay escalation by 4 weeks
• Some patients achieve adequate response at submaximal doses and may continue long-term 2

Missed Dose Management 1:

• If next dose >48 hours away: Administer as soon as possible
• If next dose <48 hours away: Skip and resume regular schedule
• If ≥2 consecutive doses missed: Resume scheduled dosing or reinitiate with dose escalation to reduce GI symptoms

Expected Weight Loss Efficacy

The STEP trial program demonstrates substantial weight reduction 3, 4, 5:

• STEP 1 (68 weeks, non-diabetic): -14.9% body weight vs -2.4% placebo (difference -12.4%) 6
• STEP 5 (104 weeks): -15.2% vs -2.6% placebo, demonstrating sustained long-term efficacy 7
• STEP 2 (68 weeks, with type 2 diabetes): -9.6% vs -3.4% placebo 8, 4

Clinically meaningful weight loss thresholds 3, 6:

• 86.4% achieved ≥5% weight loss (vs 31.5% placebo)
• 69.1% achieved ≥10% weight loss (vs 12.0% placebo)
• 50.5% achieved ≥15% weight loss (vs 4.9% placebo)

Real-world data shows mean weight loss of -13.6% at 12 months in primary care, though with higher discontinuation rates and slower titration than trials 9.

Absolute Contraindications

Do not prescribe Wegovy in patients with 1:

1. Personal or family history of medullary thyroid carcinoma (MTC)
2. Multiple Endocrine Neoplasia syndrome type 2 (MEN 2)
3. Prior serious hypersensitivity reaction to semaglutide (anaphylaxis, angioedema)

Pregnancy and breastfeeding: Contraindicated; discontinue at least 2 months before planned pregnancy due to long half-life 3

Critical Safety Warnings

Thyroid C-Cell Tumors (Black Box Warning)

Semaglutide caused dose-dependent thyroid C-cell tumors in rodents 1. While human relevance is uncertain, counsel patients about neck mass, dysphagia, dyspnea, or persistent hoarseness. Routine calcitonin monitoring is of uncertain value and may lead to unnecessary procedures 1.

Acute Pancreatitis

Observe for persistent severe abdominal pain (may radiate to back) with or without vomiting. Discontinue immediately if pancreatitis suspected 2, 1. Incidence <0.1% in post-marketing surveillance 2.

Acute Gallbladder Disease

Cholelithiasis reported in 1.6% of adults (higher in pediatric patients) 1. Risk increases with rapid weight loss. Monitor for right upper quadrant pain, nausea, and fever 3, 2.

Gastrointestinal Adverse Events

Most common side effects (typically transient, mild-to-moderate) 3, 2, 10:

• Nausea (40% vs 14.8% placebo)
• Vomiting (16% vs 4.3% placebo)
• Diarrhea, constipation, abdominal pain
• 4.5% discontinued due to GI events vs 0.8% placebo 2

Gradual dose titration significantly reduces GI symptoms 2.

Special Populations and Drug Interactions

Renal Impairment

No dose adjustment required for any level of renal function 11. However, use caution when initiating or escalating doses due to potential acute kidney injury from dehydration secondary to GI adverse effects 10, 1.

Type 2 Diabetes

• Reduce insulin and sulfonylurea doses to minimize hypoglycemia risk 2
• Monitor blood glucose before starting and during treatment 1
• GLP-1 RAs stimulate glucose-dependent insulin secretion, carrying very low intrinsic hypoglycemia risk 2

Drug Interactions 2:

• Do not combine with other GLP-1 receptor agonists or DPP-4 inhibitors
• May delay gastric emptying, affecting absorption of oral medications requiring rapid onset
• Monitor oral contraceptives, warfarin, and medications with narrow therapeutic index

Monitoring Recommendations

Before initiating 3, 2, 1:

• Baseline weight, BMI, waist circumference
• Blood pressure, heart rate
• Lipid panel, HbA1c (if diabetic or prediabetic)
• Pregnancy test in women of childbearing potential
• Screen for personal/family history of MTC or MEN 2

During treatment:

• Weight and vital signs at each dose escalation and quarterly thereafter
• Blood glucose monitoring if diabetic
• Assess for GI symptoms, particularly during titration
• Monitor for signs of pancreatitis, gallbladder disease
• Evaluate for thyroid symptoms (though routine calcitonin monitoring not recommended)

Discontinuation criteria 3:

• After 3-4 months at maintenance dose, discontinue if inadequate response (though specific threshold not defined in FDA label, clinical judgment recommended)
• Serious adverse events (pancreatitis, severe hypersensitivity)
• Pregnancy

Cardiovascular Benefits

The SELECT trial demonstrated that in 17,604 adults with established CVD, BMI ≥27, and without diabetes, semaglutide 2.4 mg reduced 3-point MACE by 20% (HR 0.80,95% CI 0.72-0.90) over mean 40-month follow-up 4, 5. This led to FDA approval for secondary CV risk reduction 4, 1.

Additional cardiometabolic improvements include reductions in blood pressure, atherogenic lipids, inflammatory markers (CRP), and UACR 8, 4.

Common Clinical Pitfalls

1. Rushing dose escalation: Increases GI adverse events and discontinuation. Stick to monthly escalation schedule 2
2. Not counseling on GI effects: Patients should expect transient nausea/vomiting that typically resolves with time
3. Forgetting insulin/sulfonylurea adjustment: Can cause severe hypoglycemia in diabetic patients 2
4. Inadequate contraception counseling: Long half-life requires 2-month washout before pregnancy 3
5. Expecting uniform response: Weight loss varies; some patients respond adequately to submaximal doses 2, 12

Practical Implementation

Patient selection priorities 2:

• Semaglutide may be prioritized for patients with established CVD given proven MACE reduction
• Consider in patients with multiple cardiometabolic comorbidities
• Preferred in patients with type 2 diabetes given dual glycemic and weight benefits
• Alternative to liraglutide for patients preferring weekly vs daily injections

Cost and access considerations: Average wholesale price ~$1,619/month 10. Insurance authorization challenges are common; document BMI, weight-related comorbidities, and prior lifestyle intervention attempts 2.

Long-term use required: Weight regain occurs after discontinuation (mean 11.6% regain at 52 weeks post-treatment) 5. Counsel patients that this is chronic disease management requiring indefinite treatment 2.