At Levity, we understand that starting weight loss medication is an exciting step in your weight loss journey but like any other medication it’s important to understand the side effects that it can cause as well as how to effectively manage them.
Here our experts unpack the most common side effects caused by weight loss medication but the good news is that they are usually mild and easily managed.
Constipation is a very common side effect of weight loss medications, affecting more than 1 in 10 users. [1-2] You may be experiencing constipation if you are having trouble passing stool, have passed stool fewer than 3 times in a week or your stools are hard, dry and lumpy. This happens because weight loss medications work by keeping you fuller for longer and slowing down the rate at which your stomach empties meaning they can also cause a delay in bowel movements.
To ease constipation we recommend including more fibre-rich foods in your diet like prunes, figs and oats as well as staying hydrated. You might also find that going for a walk or using stool softeners or other over-the-counter remedies may help relieve symptoms.
Another common side effect associated with the use of weight loss medication is headaches. [1-2] The good news is that not everyone will experience headaches and they are generally manageable and do not typically require you to stop using treatment. You can manage headaches by resting in a quiet, dimly-lit space, making sure you get 7-9 hours of sleep and using medications like paracetamol.
In some cases weight loss medications can cause increased intestinal motility which means that food and waste move too quickly through your digestive tract—causing diarrhoea. [3]
To manage diarrhoea we recommend using oral rehydration salts to help replace lost fluids and electrolytes and pain relievers like paracetamol to help with discomfort.
Heartburn, also known as acid reflux, is a burning sensation in the chest that occurs when stomach acid flows back into the food pipe leading to discomfort, pain, and a sour taste in your mouth. [1-2]
This happens because weight loss medications slow down the emptying of the stomach, causing stomach acid to move up to your food pipe contributing to heartburn. [4]
Many people find that eating small, frequent meals, avoiding high-fat foods and sugars and using simple oral medications for acid reflux help to alleviate this side effect.
Since the medications included in Levity’s weight loss program are administered by injection, it is important to be aware of the possible reactions that may occur at the injection site. These reactions can include redness, swelling, itching, or pain at the site of injection. [1-2]
The easiest way to prevent and manage this side effect is to rotate injection sites each time you administer your medication. You can do this by alternating between different areas on the body such as the abdomen, thigh, or upper arm or simply choosing a different position at the same injection site.
If you do experience injection site reactions, you can apply a cold compress to the affected area which can help reduce swelling and pain as well as use non-drowsy antihistamines or local antihistamine creams.
Fatigue is characterised by a persistent feeling of tiredness, weakness, or lack of energy that can significantly impact how you perform daily activities and your quality of life. The onset and severity of fatigue is different for everyone, with some people experiencing mild symptoms that resolve over time, while others struggle with more persistent symptoms. [2]
If you are experiencing fatigue while taking weight loss medication, it is important to make sure you are getting enough sleep, staying hydrated and eating enough nutrient dense food to fuel your body.
Nausea and vomiting are some of the common side effects associated with the use of weight loss medications due to the direct effects of the medication on the central nervous system. [1-2]
A lot of people find nausea to be particularly intense when they start treatment or after they increase their dose while their body adapts to the medication.
To help alleviate nausea, we recommend staying hydrated, avoiding strong smells and eating crackers, mint, or ginger-based foods or drinks about half an hour after taking medication. Eating slowly and stopping when full can also help reduce the likelihood of experiencing nausea and some patients also find that having more frequent meals in smaller amounts can help manage vomiting symptoms.
If you are still finding nausea difficult to manage you can discuss your symptoms with the Levity clinical team and explore whether moving to a lower dose may be beneficial for you.
While weight loss medications are proven to be highly effective for diabetes and weight management, it is important to be aware of the serious side effects associated with these medications. Although rare, some individuals may experience complications that require immediate medical attention.
One of the serious side effects of weight loss medications is pancreatitis, which is characterised by inflammation of the pancreas. The pancreas is located behind the stomach and is crucial for healthy digestion and blood sugar regulation. Symptoms of pancreatitis include severe abdominal pain, nausea, vomiting, and fever. Pancreatitis needs to be treated in a hospital setting and if you are worried or concerned you might have pancreatitis, it's important to stop taking your medication immediately and seek medical attention. [1-2]
In rare cases, weight loss medications have been linked to acute kidney injury because they can lead to dehydration, which reduces blood flow to the kidneys. Symptoms of sudden changes in kidney function include decreased urine output and swelling in the legs. [1-2]
Like any medication, weight loss medication can cause severe allergic reactions or in rare cases anaphylaxis (a life-threatening allergic reaction that happens very quickly). Symptoms of anaphylaxis may include shortness of breath or wheezing, hives, difficulty swallowing, and a red rash. [1-2]
To seek immediate medical attention for any of the above you can call 999, you should also inform the Levity clinical team about any serious side effects or reactions once you have been treated.
While not technically considered a side effect, in some cases patients may not experience the desired weight loss or outcomes from treatment.
Sometimes, a lack of results can be caused by common side effects like nausea, vomiting, diarrhoea, and constipation because they impact your ability to tolerate and adhere to treatment. In other cases, factors such as underlying health conditions, genetic predispositions, lifestyle habits, and medications can influence how you respond to weight loss medication. [5] This is why it's essential to work with our Levity team to find the most effective treatment you can tolerate with minimal side effects. If you have any questions or concerns about how quickly you are seeing results, please reach out to our Levity clinical team for assistance.
Remember, if you’re experiencing severe side effects or a severe allergic reaction, you can seek immediate medical attention by calling 111 or 999.
Finally, our Levity clinical team is here to support you during your weight loss journey. If you have any questions or concerns about side effects or how to manage them, don’t hesitate to contact us.
[1] HIGHLIGHTS OF PRESCRIBING INFORMATION [Internet]. Available from: https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/215866s000lbl.pdf
[2] HIGHLIGHTS OF PRESCRIBING INFORMATION [Internet]. Available from: https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/215256s005lbl.pdf
[3] Wharton S, Davies M, Dicker D, Lingvay I, Mosenzon O, Rubino DM, et al. Managing the gastrointestinal side effects of GLP-1 receptor agonists in obesity: recommendations for clinical practice. Postgraduate Medicine. 2021 Nov 29;134(1):14–9.
[4] Liu BD, Udemba SC, Liang K, Tarabichi Y, Hill H, Fass R, et al. Shorter-acting glucagon-like peptide-1 receptor agonists are associated with increased development of gastro-oesophageal reflux disease and its complications in patients with type 2 diabetes mellitus: a population-level retrospective matched cohort study. Gut [Internet]. 2023 Sep 22 [cited 2023 Oct 19]; Available from: https://gut.bmj.com/content/early/2023/09/21/gutjnl-2023-329651
[5] Ozempic: 5 Reasons People Don’t Lose Weight on GLP-1 Drugs [Internet]. Healthline. 2024. Available from: https://www.healthline.com/health-news/ozempic-glp-1-drugs-may-not-work
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