Nausea
- Eat smaller, more frequent meals
- Avoid rich, spicy, or fatty foods
- Stay hydrated!
- Take anti-sickness medication if needed
Side effects occur because weight loss injections influence how your body processes food, appetite, and digestion. These medications work by slowing the rate of food leaving the stomach and affecting hunger hormones, which can sometimes lead to digestive changes, fatigue, or nausea. While most side effects are mild and temporary, knowing how to handle them can help make your treatment more comfortable and effective.
"Side effects are normal, and most can be managed at home without interrupting your treatment. Below are the most common side effects, the best ways to handle them, and when you should speak to your doctor."
Weight loss injections slow digestion, meaning food stays in your stomach longer, which can sometimes cause nausea, especially after eating.
If nausea is persistent, worsening, or accompanied by vomiting that prevents you from keeping fluids down, it’s time to seek medical advice.
Weight loss injections can slow digestion, which may lead to constipation in some people.
If constipation becomes severe, lasts longer than a few days, or causes discomfort, bloating, or vomiting, consult a doctor for guidance.
Some people experience diarrhoea as their body adjusts to the medication, particularly if their diet has changed significantly.
If diarrhoea lasts more than a few days, becomes severe, or is accompanied by dehydration symptoms (such as dizziness, dry mouth, or dark urine), seek medical advice.
Weight loss injections impact metabolism, and as your body adjusts to a lower calorie intake, you may feel more tired than usual.
If fatigue becomes extreme, affects your daily life, or doesn’t improve, speak to a doctor to rule out any underlying causes.
In some cases, weight loss injections may cause nausea severe enough to lead to vomiting, particularly if you eat too much or too quickly.
If vomiting is severe, doesn’t improve, or is accompanied by dehydration or abdominal pain, seek medical attention.
While the above symptoms are the most common, some people may experience:
If any of these symptoms persist or become severe, consult a doctor.
While most side effects are mild, it’s important to know when to seek medical attention. Contact a doctor if:
For mild concerns, you can reach out via your ZAVA patient account, where we’re always here to help. If symptoms become severe or difficult to manage, call 111 for urgent medical advice—or 999 in an emergency.
Nausea
Constipation
Diarrhoea
Mild fatigue
Vomiting
For most people, side effects are temporary and should improve within the first few weeks of treatment. Here’s what to expect:
Most people experience at least one mild side effect when starting weight loss injections, but they usually improve as the body adjusts.
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