Medication
After consultation and assessment your Doctor may discuss the option of medication for the treatment of obesity. These medications can be helpful to support weight loss and/or weight maintenance when used in addition to healthy eating and regular physical activity. A healthy sleep pattern and support for mental and emotional health is also important while taking any weight management medication. Options include:
GLP-1 Agonists
GLP-1 agonists are medications that help with the control of hunger and fullness and also help to support healthy blood sugar levels. Examples include – Semaglutide (Ozempic, Wegovy) and Liraglutide (Saxenda, Victoza).
How do GLP-1 Agonists work?
The body naturally produces an appetite hormone known as glucagon-like peptide-1 (GLP-1) that helps to regulate hunger. GLP-1 Agonists (like Saxenda etc.) work by:
- Increasing satiety (feeling of fullness)
- Reducing hunger/ appetite
- Slowing down the movement of food through the stomach
How are GLP-1 Agonists used?
- Semaglutide is an injection that is given once per week in the fat tissue that lies just under the skin. A healthcare professional will show you the best place to inject the medication. Areas may include the tummy area, the front of your thighs and the upper arms.
- Liraglutide is an injection that is given in the same way as Semaglutide but it is given once per day.
The dose is usually increased in stages to decrease the risk of side effects. Your doctor may recommend to lower the dose if you are having significant side effects.
What are the risks associated with GLP-1 Agonists?
Many patients use GLP-1 agonists without side effects. Your doctor will discuss with you possible side effects before starting the medication.
Common side effects can include:
- feeling sick (nausea) and diarrhoea (these symptoms usually go away with time)
- constipation
- mild stomach pain
If you do find your tummy is upset, you may find the following tips helpful:
- Eat smaller meals
- Eat slowly, and stop eating as soon as you feel you start to feel full. This may mean you do not eat all the food on your plate
- Try not to overeat
- Avoid greasy foods
- Do not lie down immediately after eating
There is the potential risk for more serious side effects, these can include:
- Pancreatitis (inflammation of the pancreas). If you have severe and long lasting stomach pain (which might reach through to your back), with or without being sick (vomiting) contact a doctor immediately.
- Gallstones (stones that can develop in your gallbladder). There is a higher risk of developing gallstones with rapid weight loss.
- Low blood sugar (hypoglycaemia). This can only happen if you are also taking other diabetes medications, such as sulphonylureas (Gliclazide) or Insulin. If this happens, you should contact your GP or diabetes team and they will advise you about reducing the dose of these medications.
If you have diabetes it is important that retinal screening (eye test where they take a photo of the back of the eye) is up to date. Please tell your healthcare professional if there are any concerns about your eyes before you start GLP-1 agonist medications.
GLP-1 agonists should not be prescribed to any woman who is pregnant or planning a pregnancy.
If you have any concerns or questions about side effects please speak with a healthcare professional.
How long does it take GLP-1 Agonists to work?
Patients will respond differently to obesity treatment medications. Some people will lose weight quickly, some people will lose weight more slowly and some people will not lose any weight. If you do have weight loss, this will start to level out, usually around 6-12 months after starting the medication, but this is different for every patient. When this levelling out point, or ‘weight plateau’, is reached, you should continue the medication to maintain this weight and prevent weight regain.
You should have a follow up appointment with the doctor who prescribed the GLP-1 agonist, to assess the benefits of the medication, discuss any problems or side affects you may be experiencing, and to decide if you should continue the medication. This should happen 3-4 months after starting the medication, or up to 6 months if you were taking a lower dose for longer.
Naltrexone/ Bupropion (Mysimba)
How does Mysimba work?
Mysimba contains two medications – naltrexone and bupropion. They work together in parts of the brain that control food intake and energy balance. They can reduce the effect of the part of the brain that controls pleasure associated with eating food.
How is Mysimba used?
Treatment with Mysimba is started with one tablet each morning and the dose is gradually increased over 4 weeks, until you are taking 4 tablets daily, 2 in the morning and 2 in the evening. Mysimba should be taken with food.
What are the risks associated with Mysimba?
Common side effects with Mysimba can include:
- Nausea or vomiting
- Constipation
- Dizziness
- Dry mouth
Mysimba can cause an increase in blood pressure (BP) and/or heart rate. Mysimba should not be started in patients with high BP that is not well controlled.
There are some other groups of patients for whom this medication may not be suitable. Your doctor will consider a range of factors such as kidney and liver function, if you had a seizure in the past, and if you are taking medications that may interact with Mysimba. Mysimba is not recommended for people with certain mental health conditions. Your suitability for this medication can be discussed with your doctor.
How long does it take for Mysimba to work?
You should have a follow up appointment with the doctor who prescribed this medication 4 months after starting it. They will recommend stopping the medication if you have not lost at least 5% of initial body weight.
Orlistat/ Xenical
How does Orlistat work?
Orlistat works by blocking chemicals known as enzymes in your gut which break down fat. It stops about a third of the fat that you eat from being absorbed in the gut. The undigested fat that is not absorbed into your body is passed out with your stools (faeces).
How is Orlistat used?
Orlistat is taken as a tablet immediately before, during or up to one hour after each main meal. It is recommended that you are eating healthy low fat food.
Ideally the use of Orlistat should be in conjunction with nutritional support or guidance from a dietitian. Before taking Orlistat there should be a review of how you are currently eating, and how to spread your daily fat intake over your three main meals.
What are the risks associated with Orlistat?
The main side effect is the possibility of significant stomach upset (mainly diarrhoea). This increases when orlistat is taken with a diet high in fat. This is why a nutritional assessment before starting this medication is highly recommended.
How long does it take Orlistat to work?
Your response to Orlistat will be assessed by your doctor. They will assess if you have lost about 5% of initial body weight 12 weeks after starting the medication.
If you already have a low fat diet prior to starting Orlistat there may not be any weight loss.