Overview

• Deborah Grayson says some patients develop long‑lasting gastrointestinal symptoms that persist after discontinuing the injections, as roughly 1.5 million Britons use these drugs.
• She identifies gastroparesis as the key issue, noting the medicines intentionally slow gastric emptying to promote fullness, which can in some cases lead to prolonged digestive problems.
• Manufacturer information lists delayed gastric emptying as an uncommon side effect, and Lilly advises Mounjaro is not recommended for patients with severe gastroparesis, with trials showing more severe gastrointestinal events than placebo.
• The MHRA has received hundreds of reports of acute and chronic pancreatitis in people using GLP‑1 medicines, though these reports are not confirmed as caused by the drugs.
• NHS guidance urges people with symptoms such as early fullness, nausea, vomiting, bloating, persistent heartburn, or ongoing stomach pain to see a GP and consider dietary measures for suspected gastroparesis.