Common Negative Effects of GLP-1 Injections - Is semaglutide really the quick fix?

Metabolic-Health@outlook.com
4 days ago
2 min read

GLP-1 receptor agonists (e.g., semaglutide, liraglutide, dulaglutide) are widely used for type 2 diabetes and obesity. While effective for weight loss and blood sugar control, they also come with potential side effects and risks. Like any side effects from taking a drug, these need to be explained and understood before starting the medication.

The first lots of side mostly related to gastrointestinal issues and are typically very common with taking GLP-1 receptor agonists. These include nausea (up to 40%), vomiting, diarrhea, constipation and bloating. There is of course, loss of appetite and eating discomfort. While intentional for weight loss, some users report - inability to eat normal portions and aversion to food.

In addition, there is a real risk of undernourishment. This is the one of the most worrying of side effects as the as rapid weight loss can include muscle mass loss, not just fat. Important to combine with adequate protein intake and resistance exercise to try and off-set this.

Its worth noting that 25–40% of total weight loss can come from lean body mass, mainly skeletal muscle. This is concerning because: Muscle is essential for metabolism, strength, mobility, and insulin sensitivity. Rapid or excessive muscle loss can increase frailty, especially in older adults. Bone density loss is also a concern with long-term calorie restriction and weight loss. A review paper of 28 clinical trials showed that using a GLP-1RA-based agent resulted in a lost of lean mass between 20% and 40%.

GLP-1 injections are highly effective but come with real side effects, especially gastrointestinal and gallbladder-related. The loss of lean (muscle) mass is a very worrying side effect and could open up the pathway for whole body insulin resistance and the associated metabolic conditions that come with this. Monitoring and a slow dose escalation schedule help manage many of these risks.

There are some more side effects explained below.

Gallbladder Issues

Increased risk of gallstones and gallbladder inflammation, especially during rapid weight loss.
May require gallbladder removal in rare cases.

Pancreatitis (Rare but serious)

Some studies link GLP-1 agonists to acute pancreatitis, though the evidence is not conclusive.
Patients with a history of pancreatitis may be advised to avoid these drugs.

Potential Thyroid Cancer Risk (in animals)

Rodent studies showed a risk of medullary thyroid carcinoma (MTC).
Black box warning for patients with:
- Personal/family history of MTC
- MEN2 syndrome (Multiple Endocrine Neoplasia type 2) (No strong evidence of increased thyroid cancer in humans so far).

Injection Site Reactions