New Delhi: The discontinuation of anti-obesity drugs can lead to weight gain eight weeks later. In a paper published in BMC Medicine titled  ‘Trajectory of the body weight after drug  discontinuation in the treatment of anti-obesity medications’, the authors say that weight continues to decrease till four weeks after discontinuation, only to begin to show a gradually increasing trend after eight weeks. The study was published on July 22, 2025.

The authors – Han Wu, Wenjia Yang, Tong Guo, et al. – say that six months after discontinuation of treatment, the trajectory of weight regain levels off – i.e. significant weight regain might happen in the first six months after discontinuation of anti-obesity drugs.

The authors have looked at various ways in which weight can be lost, and then gained back after the discontinuation of such methods. For example, a 10-year observational study suggested that only 25% of patients who lost weight on a low-calorie diet maintained weight loss. 

Another popular strategy to lose weight is bariatric surgery, done to reduce body fat mechanically. Those who underwent these surgeries “regained an average of more than 5% from their lowest weight at 15 years of follow-up", the authors say citing other studies. 

Therefore, weight gain after the initial phase of weight loss is common. ”It is necessary to establish long-term anti-obesity treatment in clinical practice,” the authors say. 

Doctors also say that anti-obesity drugs are powerful tools but they are no magic bullets. 

Many other studies have been pointing this out for a long time now. In this study published in the Journal of American Medical Association in January 2024, the researchers found that in participants with obesity or who were overweight, withdrawing tirzepatide, an anti-obesity drug, led to substantial regaining of lost weight. On the other hand, those who continued treatment maintained and augmented initial weight reduction.

Thus, the discontinuation of this drug was directly responsible for weight gain. 

Authors of the BMC Medicine study said that due to certain limitations, they could not conclusively determine the association between rate of weight reduction and weight regain. Anoop Misra, director of the National Diabetes Obesity and Cholesterol Foundation believes that what this study fell short of explicitly saying is that weight regain is never to the same extent as to take patients to their weight prior to starting medications. The gain is always 10-20% of the weight reduced. 

Advantages of anti-obesity drugs

Misra shared an example of one of his patients who consumed tirzepatide, and lost 20 kg with continuous use. The patient stated to Misra that he was not able to walk previously even for 500 meters without breathlessness After continued and long term intake of the drug he could walk 5 km in one go. “I am reborn,” the patient told him. 

Dr Ambrish Mithal, chairman and head of endocrinology and diabetes unit at Max Healthcare, says that these drugs are ‘fascinating’ for clinicians. The fact that semaglutide (an anti-obesity drug) reduces weight by 10-25% is “quite something,” he said.

However, one key rider here is the necessity of continued intake of these drugs and the fact that they are costly. Novo Nordisk’s Wegovy, which has the brand name of semaglutide, costs up to Rs 26,050 per month. 

When asked if pharma firms would ever have a strategy change considering the disadvantages, NODC's Misra said, they would continue prioritising the production of these drugs over others. 

“There is a need for the pharma industry, regulators, and healthcare providers to align expectations: these are not quick-fix solutions, but chronic [long-term] therapies for a chronic condition,” he said. Misra says all stakeholders must come forward and ensure greater access of these drugs – and also their affordability, He hopes semaglutide will be off patent next year, thus facilitating the availability of cheaper version of this drug,

Nonetheless, doctors also warn that any anti-obesity drug must not be considered a miracle. “They can be only one part of weight reduction or diabetes management programmes. It [an anti-obesity drug] is not like an aspirin that one can simply pop at will,” said Mithal.

NDOC's Misra also advises that people with obesity consider these drugs as only one part of a comprehensive, long-term treatment strategy – alongside lifestyle modification, regular medical follow-up, and, when needed, psychological support.

Disadvantages

The process of regaining weight after treatment discontinuation is called ‘weight cycling – that is the repeated process of weight loss and weight gain,’ the paper published in BMC medicine says. 

It has been theorised that weight cycling may be related to a variety of factors. A 10-week study with a very low energy diet shows that weight loss induces adverse gut hormonal changes 

Thus, this adverse hormonal change in the gut causes an increase in hunger levels and the urge to eat, which promotes weight regain. 

As a considerable amount of literature – like the BMC Medicine and JAMA papers – clearly establishes weight gain after drug discontinuation, therefore, to prevent regain, one becomes dependent on these drugs for a very long time, just like diabetes and anti-hypertensive drugs.

Secondly, once one starts taking these drugs, rapid weight loss happens. Mithal says this may lead to loss of muscle mass. He warns that even if one puts on weight later, the lost muscle mass will not come back. So you will have more fat and less muscle.

Loss of muscle mass is significant as it can impair movement, make one prone to falls and fractures and impact overall body functions due to frailty.

Indians, as we know, have poor muscle mass already because of poor protein intake, Mithal said. 

“[To avoid loss of muscle mass] these drugs have to be used very carefully under strict medical supervision and should not be available over the counter,” he advised.

Mithal prescribes another sustainable strategy to lose weight –  exercising with adequate protein intake for weight reduction. This, he says, can reduce the loss of muscle mass. 

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