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4.5 Drugs used in the treatment of obesity

First Line
Second Line
Specialist
Hospital Only

For referral information, please see adult weight management pathway:

Obesity is associated with many health problems including cardiovascular disease, diabetes mellitus, gallstones and osteoarthritis. Factors that aggravate obesity may include depression, other psychological problems and some drugs.

The main treatment of the obese individual is a suitable diet, carefully explained to the individual, with appropriate support and encouragement; the individual should also be advised to increase physical activity.

Severe obesity should be managed in an appropriate setting by staff that have been trained in the management of obesity; the individual should receive advice on diet and lifestyle modification and be monitored for changes in weight as well as in blood pressure, blood lipids and other associated conditions. Drug therapy must only be offered as part of a package of care if there is demonstrated weight loss prior to treatment.

Naltrexone-bupropion
  • NICE TA494: Naltrexone-bupropion is not recommended for managing overweight and obesity in adults alongside a reduced-calorie diet and increased physical activity (December 2017)

Centrally acting appetite suppressants

Phentermine and diethylpropion are central stimulants; they are not recommended for the treatment of obesity. Phentermine has been associated with a risk of pulmonary hypertension.

Sibutramine, dexfenfluramine, and fenfluramine have been withdrawn from the market because the benefit of treatment does not outweigh the risk of serious adverse effects.

Lipase inhibitors

Orlistat
  • Capsules 120mg (£24.37 = 84 capsules)

Notes

  1. NICE CG43: (December 2006) recommends that orlistat should be prescribed under the following conditions:
    1. Part of an overall plan for managing obesity in adults who have a body mass index (BMI) of 28kg/m2 or more with associated risk factors, or
    2. a BMI of 30kg/m2 or more.
  2. Treatment should be continued beyond three months only if the person has lost at least 5% of their initial body weight since starting drug treatment (although less strict goals may be appropriate for people with type 2 diabetes).
  3. Therapy should only be continued beyond twelve months (usually for weight maintenance) only after discussing potential benefits and limitations with the patient.
  4. Co-prescribing with other drugs for weight reduction is not recommended.

Melanocortin 4 receptor agonist

Setmelanotide
  • Solution for injection 10mg in 1ml

Notes

  1. NICE HST21: Setmelanotide (Imcivree) is recommended, within its marketing authorisation, as an option for treating obesity and controlling hunger caused by pro-opiomelanocortin (POMC) deficiency, including proprotein convertase subtilisin/kexin type 1 or leptin receptor (LEPR) deficiency in people 6 years and over, only if the company provides setmelanotide according to the commercial arrangement (July 2022).

Glucagon-like peptide-1 receptor agonists (GLP-1 mimetics)

Saxenda

(Liraglutide)

  • Solution for injection pre-filled pen 6mg in 1ml

Indications

  • As an adjunct to a reduced-calorie diet and increased physical activity for weight management in adults who meet the criteria in NICE TA664 (see note 3)

Notes

  1. For information on referral to adult weight management service, please see links at top of page.
  2. Prescribe by brand (to aid identification where products contain multiple ingredients, or to prevent confusion where multiple brands contain similar ingredients and / or have different licensed indications and dosing regimens):
    1. Saxenda is licensed for weight management
    2. Victoza is licensed for the treatment of type 2 diabetes mellitus and should not be prescribed for weight management, see section 6.1.2 Antidiabetic drugs
  3. NICE TA664: Liraglutide (Saxenda) is recommended as an option for managing overweight and obesity alongside a reduced-calorie diet and increased physical activity in adults (December 2020), only if:
    1. they have a body mass index (BMI) of at least 35kg/m2 (or at least 32.5kg/m2 for members of minority ethnic groups known to be at equivalent risk of the consequences of obesity at a lower BMI than the white population) and
    2. they have non-diabetic hyperglycaemia (defined as a haemoglobin A1c level of 42 mmol/mol to 47 mmol/mol [6.0% to 6.4%] or a fasting plasma glucose level of 5.5 mmol/litre to 6.9 mmol/litre) and
    3. they have a high risk of cardiovascular disease based on risk factors such as hypertension and dyslipidaemia and
    4. it is prescribed in secondary care by a specialist multidisciplinary tier 3 weight management service and
    5. the company provides it according to the commercial arrangement
  4. The safety and efficacy of liraglutide for weight management have not been established in the following patients. Use in these patients is not recommended; aged 75 years or more, treated with other products for weight management, with obesity secondary to endocrinological or eating disorders or to treatment with medicinal products that may cause weight gain, with severe renal impairment, with severe hepatic impairment (see SmPC for more details)
  5. For use of liraglutide (Victoza) in the treatment Type 2 diabetes mellitus, see section 6.1.2 Antidiabetic drugs.
  6. MHRA Drug Safety Update (November 2023): Ozempic (semaglutide) and Saxenda (liraglutide): vigilance required due to potentially harmful falsified products
    1. Falsified Ozempic and Saxenda products have been found in the UK, including falsified pens containing insulin. Ozempic and Saxenda from legitimate supply chains are unaffected. 
    2. Remain vigilant for symptoms linked to hypoglycaemia in patients who may have obtained a falsified product.
    3. Remind patients using these products to always obtain prescription medicines from a qualified healthcare provider and not to use products they suspect are falsified. The legitimacy of a pharmacy, including those on-line, can be verified by referring to the GPhC website pharmacy registry.
    4. Refer to the safety update for additional advice to patients.
Wegovy

(Semaglutide)

  • FlexTouch solution for injection in pre-filled pen 0.25mg, 0.5mg, 1mg, 1.7mg, 2.4mg

Indications

  • As an adjunct to a reduced-calorie diet and increased physical activity for weight management, including weight loss and weight maintenance, in adults who meet the criteria in NICE TA875 (see note 3)

Notes

  1. For information on referral to adult weight management service, please see links at top of page.
  2. Prescribe by brand (to aid identification where products contain multiple ingredients, or to prevent confusion where multiple brands contain similar ingredients and / or have different licensed indications and dosing regimens):
    1. Wegovy is licensed for weight management
    2. Ozempic and Rybelsus are licensed for the treatment of type 2 diabetes mellitus and should not be prescribed for weight management, see section 6.1.2 Antidiabetic drugs
  3. NICE TA875: Semaglutide (Wegovy) is recommended as an option for weight management, including weight loss and weight maintenance, alongside a reduced-calorie diet and increased physical activity in adults (March 2023), only if:
    1. it is used for a maximum of 2 years, and within a specialist weight management service providing multidisciplinary management of overweight or obesity (including but not limited to tiers 3 and 4), and
    2. they have at least 1 weight-related comorbidity and:
      1. body mass index (BMI) of at least 35.0kg/m2, or
      2. BMI of 30.0kg/m2 to 34.9kg/m2 and meet the criteria for referral to specialist weight management services in NICE's guideline on obesity: identification, assessment and management and
    3. the company provides it according to the commercial arrangement.
    4. Use lower BMI thresholds (usually reduced by 2.5kg/m2) for people from South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family backgrounds
    5. Consider stopping semaglutide if less than 5% of the initial weight has been lost after 6 months of treatment
  4. No dose adjustment needed in elderly patients, hepatic impairment, or those with mild to moderate or severe renal impairment. Semaglutide is not recommended for use in patients with end-stage renal disease (see SmPC for more details).
  5. For use of semaglutide (Ozempic or Rybelsus) in the treatment Type 2 diabetes mellitus, see section 6.1.2 Antidiabetic drugs