Diabetes Injections Used for Weight Loss — What Are They, How Do They Work, and Are They Safe?

Obesity — the greatest health problem of our time

Obesity is a complex disease involving an excessive accumulation of body fat. It usually results from inherited factors combined with an unhealthy diet and inactivity. Cardiovascular diseases, diabetes, high blood pressure, and some cancers are among the health problems whose risk is increased by this medical condition. Obesity is even one of the main risk factors for severe COVID-19 illness.

What are the main causes of obesity?

There are many reasons people struggle with weight management:

• Genetic makeup can affect how food is converted into energy and how fat is stored.
• Metabolism can slow with increasing age.
• Insufficient sleep and stress can cause hormonal changes that increase your appetite.
• Weight gained during pregnancy can be difficult to lose, and

all of these can result in obesity.

What are the most effective methods for losing weight?

• Dietary changes (switching to a healthy diet),
• increased physical activity, and
• behavioral changes are the most important methods that may be effective in helping you lose weight.

Prescription weight-loss medications, bariatric (obesity) surgery, and devices used to treat obesity are additional options. Alongside these, research indicates that some medications used for diabetes may be used to treat obesity.

Treating obesity with injections developed for type-2 diabetes

Weight loss is an important goal of type 2 diabetes treatment. A study published by Mayo Clinic experts showed that a medication used to treat type 2 diabetes was effective for weight loss in obese people without diabetes.

According to a randomized, double-blind, placebo-controlled study published in Lancet Gastroenterolgy & Hepatology, liraglutide at the approved dose of 3 milligrams per day for three months produced an average weight loss of 5.5 kilograms. Liraglutide is the name of the active ingredient in a medication used to treat type 2 diabetes. Victoza is the name under which this medication is produced. It belongs to the class of GLP-1 receptor agonists. GLP-1 is a hormone naturally present in the intestine. It increases insulin secretion in the body. These medications are a synthetic form of this hormone.

Many GLP-1 agonists are available on the market. The table below shows those approved by the US Food and Drug Administration (FDA) and those authorized for use in Turkey.

GLP-1 receptor agonists

Which diabetes injections are used for weight loss?

Victoza (Liraglutide) is not covered by US healthcare reimbursement for obese people without type 2 diabetes. The manufacturer therefore produced a second medication with the same active ingredient under the name Saxenda, categorizing it as a weight-loss medication. The result is the same medication under two different names for two main purposes.

The only difference between Victoza and Saxenda is their dosage. Doses for patients using Victoza can be gradually increased to 1.8 milligrams. When prescribed specifically for weight loss, Saxenda can be adjusted up to 3 milligrams per day. Liraglutide (Victoza, Saxenda) is administered once daily. To ensure gastrointestinal tolerability, treatment starts at low doses and aims to reach the target dose (starting at 0.6 mg and increasing up to 3 mg).

The FDA has approved liraglutide for weight management in adult patients, used alongside a low-calorie diet and an appropriate exercise program, as an adjunctive medication. The FDA criteria for use are as follows: obese people with a body mass index above 30, overweight people with a body mass index above 27, and people with a body mass index above 27 and at least one weight-related complication (such as hypertension or type 2 diabetes).

Dulaglutide (Trulicity) is prescribed primarily for people who need to lower their blood sugar; weight loss is an additional benefit. There are 2 dosage forms: 0.75 mg and 1.50 mg. Dulaglutide (Trulicity) is administered weekly. Administration on the same day, and even at the same time, each week is recommended.

Liraglutide- and dulaglutide-derived medications work by stimulating insulin secretion and suppressing glucagon secretion in a glucose-dependent manner. They help control both fasting and post-meal blood sugar levels. It should be remembered that liraglutide and dulaglutide are not appropriate for treating type 1 diabetes.

How do weight-loss injections help you lose weight? Mechanism of action

These medications work like the GLP-1 hormone released from the small intestine during and after meals. Their mechanisms of action are as follows.

• They slow the rate at which food leaves the stomach. This helps prevent your blood sugar from rising.
• They help prevent your liver from producing and releasing too much sugar (glycogen).
• They help your pancreas produce more insulin.

Slower stomach emptying is what causes weight loss in people without diabetes. The most notable side effect reported by patients is nausea. They are advised to eat less at meals to reduce nausea. The medications are generally prescribed to obese patients for 6 months. Patients are assessed after 2 months of use, and a decision is made about whether to continue treatment.

Side effects and precautions

There are concerns that liraglutide causes thyroid cancer and pancreatitis. In one study, mice received eight times the dose given to humans, and liraglutide caused a statistically significant increase in thyroid tumors. However, the clinical significance of this finding is unknown.

The FDA says that serum calcitonin levels, a biomarker for medullary thyroid cancer, increase slightly in patients taking liraglutide. However, because this increase remains within normal limits, it states that 15 years of research would be needed to link the medication to thyroid cancer.

In 2013, a group of researchers at Johns Hopkins reported a significant association between patients hospitalized for acute pancreatitis and patients previously treated with GLP-1-derived medications. The US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) reviewed all data on this association. In a joint letter published in the New England Journal of Medicine, both groups reported that there was no evidence proving these medications increased the risk of pancreatitis or pancreatitis cancer. Although this provided reassurance about the medications, both groups regarded it as a ‘risk’ factor until more data became available.

Studies of dulaglutide in mice showed an increased incidence of thyroid C-cell tumors. It is unknown whether it causes thyroid C-cell tumors, including medullary thyroid cancer, in humans. Dulaglutide is not recommended if the patient has a family history of medullary thyroid cancer or has multiple endocrine neoplasia syndrome type 2 (MEN 2).

Summary and conclusion

First, these medications have no miraculous effect. Losing weight has become easier because patients are not hungry between meals. Some patients have regained weight after stopping medication. Others have succeeded in completely changing their metabolism and maintaining the habit of eating less. Liraglutide and dulaglutide may be effective tools for weight loss. They offer promise for treating obesity, a global health problem. Their use has been approved by the US Food and Drug Administration (FDA). Many are authorized for use in Turkey. When it comes to obesity and its treatment, the solution is complex and takes time. Whatever the treatment, it should be remembered that it must be used alongside an appropriate diet and exercise program. You should decide on the use of diabetes injections for weight loss only after consulting an endocrinologist.