4.5.1 Anti-obesity drugs acting on the gastro-intestinal tract

ChoiceDrugDosage
1st choiceNon-pharmacological treatment - diet and lifestyle changes
2nd choiceOrlistat capsules 120mgDose:
120mg taken immediately before, during, or up to 1 hour after each main meal (max 120mg 3 times daily); max period of treatment 2 years. Omit dose if meal is missed or contains no fat

Prescribing Notes

  • Refer to NICE CG189 Obesity: identification, assessment and management of overweight and obesity in children, young people and adults.
  • Pharmacological treatment should be considered only after dietary, exercise and behavioural approaches have been started and evaluated.
  • Drug treatment may be considered in patients as part of an overall treatment plan for managing obesity, who have a BMI ≥30kg/m2 or BMI ≥28kg/m2 plus associated risk factors.
  • Patients should be informed that drug therapy will be discontinued after 3 months if they fail to lose 5% of their initial body weight since starting drug treatment (less strict goals may be appropriate for people with type 2 diabetes). Further courses should only be considered after a suitable period and patients should again demonstrate the ability to lose weight on a suitable diet.
  • Continue for longer than 12 months (usually for weight maintenance) only after discussing potential benefits and limitations with the patient.
  • Common side-effects with orlistat may be limited by dietary compliance (i.e. decreased fat intake).
  • Orlistat (60mg and 120mg) has been linked to cases of oxalate nephropathy and pancreatitis. Interactions with levothyroxine and epileptic drugs have also been reported (MHRA, Drug Safety Update February 2010).
  • Orlistat is available to buy over the counter (OTC) from pharmacies under the brand name Alli®. It is licensed for those with a BMI >28kg/m2, and is available as 60mg capsules.

Caution

  • Orlistat (60mg and 120mg) has been linked to cases of oxalate nephropathy and pancreatitis. Interactions with levothyroxine and epileptic drugs have also been reported (MHRA, Drug Safety Update February 2010).