Safety considerations before taking the medicines
Please be aware there have been reports of potential misuse of anti-obesity
medicines for unauthorised indications, which may have contributed to several
suspected adverse drug reactions. (1)
- These medicines are prescription-only medicines to be used under medical supervision
and should only be prescribed by a registered healthcare professional. - If obtaining a private prescription (from a non-NHS prescriber), ensure that this is
dispensed from authorised sources, such as registered pharmacies, to avoid the risk of
receiving falsified medicines and experiencing adverse drug reactions.
These medicines are not intended as a short-term treatment of obesity. Long-term
use is required to maintain improvements in weight and health.
- Weight regain has been observed after stopping anti-obesity medicines. (2)
- Improvements in health (e.g. blood pressure, cholesterol, and blood glucose) may also
return to previous baseline as weight regains.
As with all medicines, the manufacturer has issued warnings, precautions and
contraindications that must be assessed before obtaining a prescription.
- If obtaining a private prescription, please provide correct, up-to-date details of your
medical history to ensure prescribing is safe, and to reduce the risk of adverse drug
reactions. - Please speak to a medical professional before you obtain a prescription if you are unsure.
Lifestyle changes
These medicines work best if you eat a balanced diet with reduced portion size and
exercise regularly.
Tips for eating a healthy balanced diet
Your appetite will reduce being on these medicines but you still need to ensure you are
achieving adequate nutrition:
- Aim to have 3 regular meals a day
- Include a source of fibre at each meal to prevent constipation
- Try to use smaller plate to reduce portion sizes
- Practice eating slowly and stop when feeling full
- Drink plenty of fluids to avoid dehydration
- Include a source of protein at each meal
Follow this link to check your portion sizes
Aim for a balanced plate like the Eatwell Guide to ensure you’re getting all the nutrients your body needs.
Common side effects
- Nausea
- Diarrhoea
- Constipation
- Vomiting
- Headache
- Feeling weak/tired
These side effects are common and usually decrease over time. Gradually increasing the dose
will help tolerate these medications.
Speak to your prescriber if you experience any of the following: - Allergic reactions
- Dizziness/light-headedness, sweating, shaking, weakness, confusion
- Increased heart rate/pulse
- Fever
- Changes in urination frequency, dark yellow urine
- Dry mouth/increased thirst
- Excessive diarrhoea or vomiting
- Worsening vision
- Development of a mass in the neck, difficulty swallowing or breathing, hoarseness
- Significant changes to mood and behaviours
- Persistent severe abdominal pain (sometimes radiating to the back). If this occurs,
discontinue and seek urgent medical care.
Please seek urgent medical attention if any of these are severe.
Managing the side effects(3)
If you feel sick you can try:
- Eating slowly and stopping when satisfied
- Eating smaller more frequent meals
- Not lying down soon after eating
- Not to be too active after eating
- Increasing fluid intake of clear fluids (in small sips, and not too much at once)
- Avoiding hot, sugary, spicy, fatty, fried, strong-smelling foods
- Getting fresh air and light exercise
- Keeping a food diary of foods and meal timings to help identify triggers.
If you are constipated, you can try:
- Eating more fibre – e.g. wholegrains, oats, fruits, vegetables, pulses, and nuts.
- Increasing physical activity
- Drinking 2-3 litres a day of water, tea, coffee, or sugar-free fluids.
If you have loose stools, you can try: - Temporarily reducing high fibre foods – gradually reintroduce them upon improvement in
symptoms - Drinking plenty of clear fluids to replace fluids lost
- Reducing dairy products, coffee, alcohol, laxatives and products containing sweeteners
ending in “ol” (e.g. sorbitol, mannitol, xylitol, maltitol).
If vomiting or diarrhoea is severe and persisting, please withhold the drug and speak to your
prescriber.
References :
(2) – https://pmc.ncbi.nlm.nih.gov/articles/PMC9542252/pdf/DOM-24-1553.pdf