Public interest in injectable weight loss treatments has intensified in recent months, with Google searches for “how does mounjaro work” and “side effects of mounjaro” rising sharply. Yet a recent survey found that around three in 10 adults had never heard of weight loss injections, revealing a major gap between curiosity and understanding.
The surge comes as more people explore medical support for weight management, including treatments such as Mounjaro and Wegovy. Both medications mimic the GLP-1 hormone that regulates appetite and digestion. They are prescription only and must be used under medical supervision.
Although they have been widely discussed during the past year, public awareness of how they work, what they involve and the risks attached remains uneven.
To help clarify what patients can expect during the early stages of treatment, digital healthcare provider ZAVA has shared guidance outlining typical experiences, common side effects and warning signs that require urgent care.
Initial Adjustment Period
The first week of treatment is often described as an adjustment phase as the body adapts to GLP-1 activity. Patients frequently report nausea, vomiting, mild digestive discomfort, fatigue or headaches. These tend to appear during the first few days.
Clinicians recommend smaller low-fat meals, avoidance of rich foods, good hydration and rest during this period. Consistency in dosing is important and medication should be taken exactly as prescribed. While symptoms can be unpleasant, most are temporary as the body becomes accustomed to the drug.
When Side Effects Peak
During the second week side effects sometimes intensify before easing. Nausea, headaches and digestive changes commonly continue but begin to settle in many cases. If symptoms remain persistent or difficult to manage, prescribers may adjust dosage or recommend a slower increase to help the body adapt.
Hydration and adequate rest remain central to managing discomfort. Clinicians emphasise that this stage varies between individuals depending on factors such as diet, activity and pre-existing conditions.
Moving Into Routine
By the third week, side effects often reduce as the medication becomes part of a regular routine. Some patients notice early benefits such as reduced appetite or feeling full sooner during meals. These effects link directly to the action of the GLP-1 hormone, which slows digestion and signals satiety to the brain.
Healthcare professionals continue to stress that medication works best alongside balanced nutrition and regular physical activity. Treatment is not intended to function in isolation and long-term results depend on sustained lifestyle habits.
When Visible Change Begins
Around the fourth week, some people begin to see early physical changes. Clinical trial evidence shows that sustained use of GLP-1 injections, combined with lifestyle changes, has led to significant weight reduction. In trials, Wegovy users lost up to 15 percent of their body weight over 68 weeks, while Mounjaro users saw at least a 22.5 percent reduction over 72 weeks.
Alongside weight loss, studies have recorded improvements in blood pressure, cholesterol and blood sugar regulation, all important markers of long-term health. These outcomes depend on close monitoring and adherence to medical guidance.
Understanding Serious Risks
Although most side effects remain mild and short-lived, clinicians emphasise the importance of recognising symptoms that require urgent medical attention. Rare but serious reactions include pancreatitis, marked by severe or persistent stomach pain that may reach the back and does not improve. Other warning signs include persistent vomiting, jaundice, fever, signs of infection, unusual weakness, difficulty breathing, wheezing or swelling of the face or throat.
Patients experiencing any of these symptoms are advised to stop treatment and seek emergency care immediately by attending Accident and Emergency or contacting the emergency services.
Expert View on Safe and Effective Use
Dr Babak Ashrafi from ZAVA said weight loss injections represented a major development in obesity treatment but must be used carefully.
“Weight loss injections like Mounjaro and Wegovy are one of the most exciting developments we have seen in obesity treatment in recent years. These medications do not just help reduce weight, they tackle one of the root causes by regulating appetite, which can be life-changing for people who have struggled with traditional weight loss methods. Clinical evidence shows that they can lead to significant, sustained weight loss and improvements in overall health, including blood pressure and cholesterol.
“But they are not a magic fix. Long-term success comes from combining these treatments with healthy eating, regular physical activity and the right support. That’s why it’s so important to use these injections under the guidance of a healthcare professional, who can monitor progress and make sure they are safe and suitable for individual needs.”
Workplace Wellbeing Strategies
The growing interest in weight loss medication has implications for workplace wellbeing teams, particularly as more employees explore clinical options for managing long-term health. Rising obesity rates, high levels of metabolic illness and increasing demand for evidence-based support mean employers are likely to encounter more questions about treatment safety, side effects and daily functioning.
Experts say wellbeing policies should encourage open discussion, signpost credible medical guidance and avoid assumptions about medication use. As these treatments continue to evolve, employers may also need to consider how side effects such as fatigue or digestive changes affect short-term performance and how supportive adjustments can be made during early treatment stages.
With public awareness still limited despite growing curiosity, clear information and safe signposting could become an important part of workplace health communication during the coming year.