Weight management
How tirzepatide works
The dual-agonist mechanism, the titration schedule, and an honest account of the first eight weeks.
Two receptors, not one
Tirzepatide activates two incretin receptors: GLP-1 and GIP. GLP-1 activity reduces appetite, slows gastric emptying and improves glucose-dependent insulin release. GIP activity contributes to insulin response and appears to influence how fat tissue handles energy, and may also reduce the nausea burden relative to GLP-1 activity alone.
In the UK, tirzepatide is a prescription-only medicine licensed for weight management and for type 2 diabetes. It can only be supplied against a prescription from a registered prescriber, dispensed by a registered pharmacy.
The titration schedule
Treatment starts at a low dose and increases in steps, typically every four weeks, with the aim of finding the lowest dose that produces a good response. Rushing this is the main driver of severe side effects, and there is no reward for doing so.
What the first weeks feel like
Most people notice appetite changes within the first week or two. Nausea, if it comes, tends to appear in the two to three days after a dose and after each increase, then settle. Constipation is common and responds to fibre, fluid and movement. Reflux and burping are frequent complaints and usually improve with smaller, lower-fat meals.
When to speak to someone
Severe or persistent abdominal pain, particularly pain radiating to the back, needs urgent medical assessment. Persistent vomiting, signs of dehydration, or symptoms of gallbladder problems should be reported promptly. So should any lump or swelling in the neck.
Storage and technique
Store in the fridge between 2°C and 8°C, out of direct light. Do not freeze. Inject subcutaneously into the abdomen, thigh or upper arm, rotating the site each week to avoid local irritation.
General information only. This article is not personal medical advice. Speak to a prescriber, pharmacist or your GP about your own circumstances.
