GLP-1 Comparison Guide: What Every Pharmacist and Provider Should Know

GLP-1 medications are changing the way we approach diabetes management and weight loss. With several options on the market—and more on the horizon—it’s important for pharmacists to understand how they compare. Here’s a straightforward breakdown of the most talked-about products: semaglutide, tirzepatide, and liraglutide.

What Are GLP-1 Medications?

GLP-1 stands for glucagon-like peptide-1, a natural hormone that helps regulate blood sugar and appetite. GLP-1 medications mimic this hormone, improving insulin release, slowing stomach emptying, and signaling fullness to the brain.

The result: better glucose control and weight loss.

1. Semaglutide

• Brand names: Ozempic® (diabetes), Wegovy® (weight loss)

• How it works: Once-weekly injection that mimics GLP-1

• Typical results: 10–15% body weight loss in clinical trials

• Common side effects: Nausea, constipation, diarrhea

• Pharmacist takeaway: Reliable and well-studied. Flexible dosing schedules available through compounding when supply or formulation gaps arise.

2. Tirzepatide

• Brand name: Mounjaro® (approved for diabetes, weight loss approval pending)

• How it works: Dual action—targets both GLP-1 and GIP receptors, making it more potent for some patients

• Typical results: 15–20% body weight loss on average

• Common side effects: Nausea, diarrhea, reduced appetite (may be stronger initially than semaglutide)

• Pharmacist takeaway: A newer option that often delivers greater results, but patients may experience more pronounced GI side effects early on.

3. Liraglutide

• Brand names: Victoza® (diabetes), Saxenda® (weight loss)

• How it works: Daily injection that mimics GLP-1

• Typical results: 5–10% body weight loss

• Common side effects: Similar GI issues—nausea, vomiting, diarrhea—but may improve with time

• Pharmacist takeaway: Proven and effective, but requires daily dosing, which can impact adherence compared to weekly options like semaglutide.

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Head-to-Head Comparison

Medication	Brand (Indication)	Dosing Frequency	Avg. Weight Loss	Key Notes
Semaglutide	Ozempic® / Wegovy®	Weekly	10–15%	Reliable, established, customizable via compounding
Tirzepatide	Mounjaro® (weight loss pending)	Weekly	15–20%	Dual mechanism, often stronger, newer option
Liraglutide	Victoza® / Saxenda®	Daily	5–10%	Effective but less convenient dosing

Choosing the Right Option

The “best” GLP-1 therapy depends on:

• Patient goals (modest vs. aggressive weight loss)

• Medical history (tolerance, comorbidities)

• Insurance coverage & cost

• Dosing preference (daily vs. weekly)

In simple terms:

• Semaglutide = dependable, weekly, well studied

• Tirzepatide = newer, often more effective, stronger side effects

• Liraglutide = proven, daily, less weight loss but good option when others aren’t available

Where Compounding Fits In

Pharmacists play a vital role in making these therapies accessible:

• Dosing flexibility: Compounded semaglutide can provide intermediate or personalized doses not commercially available.

• Supply shortages: Compounding helps maintain continuity of care when brand products are on backorder.

• Patient-centric care: Some patients may tolerate or respond better to different strengths or delivery formats.

Final Word for Pharmacists

GLP-1 medications are here to stay—and demand will only grow. By understanding the nuances between semaglutide, tirzepatide, and liraglutide, pharmacists can better counsel patients and support prescribers. With compounding and central fill services like those offered by RxConnexion, pharmacies can go beyond dispensing—helping tailor therapies that meet individual needs.

RxConnexion in partnership with several 503A and 503B facilities can help you deliver the care your patients demand. Contact us today about our Central Fill and Telemedicine programs that has revolutionized pharmacy practice.

Pharmacist