📢 Today we’ll discuss one of my favorite and most relevant metabolic topics… as always, from our own “special” perspective!
🟡 Vol. 12: The incretin effect and injectable anti-obesity medications
🍬 Glucose is a simple but highly essential carbohydrate in biology.
🧪 Insulin is the main mediator through which the body utilizes glucose as “fuel” to carry out a range of important functions.
📜 Diabetes Mellitus (DM) is defined as a disorder of carbohydrate metabolism characterized primarily by decreased insulin secretion or resistance to insulin effects.
🧐 Oral glucose administration leads to greater insulin secretion compared to intravenous glucose administration. This is mainly due to the effects of two hormones released from the intestine after a meal. They are called incretins: GLP-1 (Glucagon-like peptide-1) and GIP (Glucose-dependent insulinotropic polypeptide). Patients with DM are characterized by a significant reduction in the incretin effect.
✅ Therefore, medications were developed that mimic the effects of incretins. GLP-1 receptor agonists, as they are called — with main representatives liraglutide, dulaglutide, and semaglutide — are highly reliable and effective drugs for diabetes management. More recently, a new class of dual (GLP-1 and GIP) agonists has been approved, with tirzepatide as the main representative.
🔍 Beyond stimulating insulin secretion, incretins also exert other independent effects, such as reducing glucagon secretion (a hormone that antagonizes insulin), slowing gastric emptying, and increasing satiety. These effects lead to reduced food intake and, consequently, body weight reduction.
‼️ Thus, incretin agonists have also been employed for the treatment of obesity, independently of the presence of diabetes. Administration is via a weekly subcutaneous injection. The results are, admittedly, impressive.
Let’s have a brief summary of what currently applies in Greece regarding prescription and reimbursement of these medications.
🏥 Until recently, the only reimbursed medication for obesity was liraglutide (Saxenda), at the doses indicated for obesity. The criteria were strict — body mass index (BMI) > 40 and one additional comorbidity — and prescribing was performed only by specialized hospital Obesity Centers.
⚫️ Dulaglutide is prescribed and reimbursed under the brand name Trulicity exclusively for diabetes and has not received official indication for obesity management.
🟣 Semaglutide has been prescribed for years at doses up to 1 mg under the brand name Ozempic, but reimbursement applies exclusively for diabetes. Higher doses of 1.7 and 2.4 mg, which show better weight-loss results, are available under the brand name Wegovy, which is not reimbursed.
🟥 Tirzepatide has recently been introduced in our country under the brand name Mounjaro, which is also not reimbursed.
♨️ Through the “Prolamvano” (Prevent) program, since December 2025 free provision of Wegovy and Mounjaro has begun for eligible individuals. The process requires free cardiovascular risk blood testing followed by a free visit to a contracted physician for evaluation of results and documentation of medical data. The criteria are now less strict (BMI > 37 with one comorbidity or BMI > 40), and the process does not require visiting a specialized hospital Obesity Center.
🔛💲 Of course, many individuals with obesity have already initiated injectable medications at their own expense.
🆘 Here are some important tips!
🆗 These medications are safe and effective, with multiple beneficial effects (cardiovascular benefits, lipid reduction, etc.). ⚠️
However, close medical monitoring during treatment is required, ensuring the following:
1️⃣ Evaluation of the required laboratory testing before treatment initiation
2️⃣ Screening for contraindications before starting therapy
3️⃣ Regular laboratory re-evaluation
4️⃣ Monitoring for rare adverse effects
5️⃣ Gradual dose escalation and management of very common gastrointestinal side effects
💎 The most important messages
🔥💦 These therapies do not provide permanent results. Significant lifestyle interventions — including diet and aerobic physical activity — are also required. Treating obesity is a long journey. These medications are very useful tools in our hands, but they should not be approached as a method for rapid and definitive weight loss. The role of physicians in the proper therapeutic approach is crucial.
🔜👀 Last but not least, a brief look at the future: higher doses than those currently administered are being studied for safety and efficacy.
💊 Additionally, oral formulations of this drug class will become available soon.
ℹ️ Finally, encouraging results emerge for cotadutide, an experimental drug of a novel class based on the incretin effect — dual GLP-1 and glucagon agonists.