"Weight Loss Injections: An Overview of Ozempic and Mounjaro - their purposes and effects"
In the realm of weight loss treatments, three drugs have recently gained attention: Semaglutide (Ozempic and Wegovy), Tirzepatide (Mounjaro), and Liraglutide (Saxenda and Wegovy). These medications primarily act through agonism of glucagon-like peptide-1 (GLP-1) receptors, with Tirzepatide also targeting glucose-dependent insulinotropic polypeptide (GIP) receptors.
Mechanisms of Action
Semaglutide (Ozempic, Wegovy)
This GLP-1 receptor agonist, mimicking the gut hormone GLP-1, slows gastric emptying, reduces hunger signaling in the brain, improves insulin secretion, and lowers blood sugar. While primarily used for type 2 diabetes, Ozempic is prescribed off-label for weight loss, and Wegovy is FDA-approved specifically for weight management at higher doses.
Tirzepatide (Mounjaro)
A dual agonist of GLP-1 and GIP receptors, Tirzepatide not only activates GLP-1 pathways (like Semaglutide) but also engages GIP receptors, which may further enhance insulin secretion and weight loss, making it potentially more effective for weight loss than GLP-1-only drugs.
Liraglutide (Saxenda, Wegovy)
Another GLP-1 receptor agonist, Liraglutide suppresses appetite, slows gastric emptying, and improves metabolic parameters. Approved for weight management under brand names like Saxenda and, at higher doses, Wegovy.
Common Side Effects
Predominantly gastrointestinal symptoms, including nausea, vomiting, diarrhea, constipation, and abdominal discomfort, are the most frequent and limiting side effects across all three medications. Women may experience more frequent digestive issues and unique effects, such as menstrual cycle changes. Other side effects can include headache, fatigue, and injection site reactions.
Potential Long-Term Effects
Long-term benefits include sustained weight loss and improved cardiometabolic health, including better insulin sensitivity and reduced risks associated with obesity and type 2 diabetes. Ongoing use may carry risks such as possible gastrointestinal safety concerns due to chronic gastric slowing, though data are still emerging. Because these medications influence metabolic hormones, there may be additional effects on fertility and hormonal balance noted especially in women, though these remain under investigation. The durability and safety of long-term treatment require continuous monitoring by healthcare providers due to limited post-marketing long-term data.
In 2022, the US Food and Drink Administration fast-tracked approval of Mounjaro to treat obesity. However, the drugs only work for as long as they are taken, and people have reported gaining back all the weight they lost after stopping the drug. Additionally, the drugs, while intended for diabetics, are prescribed "off-label" in the US to people wanting to shed weight, leading to shortages for diabetics who rely on these treatments.
In the UK, Wegovy has been licensed as a weight loss drug and is now available on the NHS. Mounjaro was supposed to be available through GP surgeries and other community services from 23 June, but as of the start of August, only eight of 42 NHS Integrated Care Boards had started providing treatment to patients. The National Institute for Health and Care Excellence (NICE) recommends that people coming off the drugs should be offered "structured advice and follow-up support" to help prevent weight gain.
Research has suggested weight loss jabs could almost halve the risk of obesity-related cancers. However, the listed side effects for the drugs include serious risks such as kidney failure, pancreatitis, and thyroid cancer. Approximately 5% of people in the semaglutide trial and 6-7% in the tirzepatide trial experienced nausea, vomiting, and diarrhea severe enough to stop taking the drugs. A side effect of sudden weight loss from these drugs is "Ozempic face", where the skin on the face sags due to loss of facial plumpness.
In conclusion, while these weight loss drugs offer promising results, it is crucial to consider their potential side effects and long-term risks. Continuous monitoring by healthcare providers and follow-up support for those coming off the drugs are essential to maintain the benefits and mitigate potential drawbacks.
In light of the current landscape, it's prudent to note that while these weight loss drugs, such as Semaglutide (Ozempic and Wegovy), Tirzepatide (Mounjaro), and Liraglutide (Saxenda and Wegovy), might contribute to health-and-wellness by aiding in weight management, they also spark intriguing implications for wars against type 2 diabetes and obesity-related diseases. Despite the potential for health improvements, their use could unwittingly aggravate shortages of these medications for individuals with type 2 diabetes who require them.
Furthermore, these drugs, particularly those used for weight management like Wegovy, might have profound consequences for the scientific community, as continued research is needed to evaluate their long-term side effects on critical aspects like fertility, hormonal balance, and even the emergence of diseases such as kidney failure, pancreatitis, and thyroid cancer.
