Explainer

Who should not take these

The contraindications and interactions an online questionnaire may not catch. Worth reading before you fill one in.

Updated 2026-09-18

Disclosure: one company on this page — Coreage Rx — pays us a commission when a reader signs up through our link. It does not buy a better score, a higher ranking, or the removal of any criticism. The scoring rubric and the full disclosure are both published.


Most online intake forms are short. Some are very short. This is the information a pharmacist would raise with you across the counter, and it is worth having in mind before you answer a questionnaire that may not ask.

This is general information and not a substitute for a clinician who has taken your full history. If any of it applies to you, say so explicitly on the intake form rather than assuming the questionnaire covers it.

Reasons these drugs are generally not prescribed

  • A personal or family history of medullary thyroid carcinoma, or Multiple Endocrine Neoplasia syndrome type 2.
  • A previous serious hypersensitivity reaction to the drug or its components.
  • Pregnancy, trying to conceive, or breastfeeding.
  • A history of pancreatitis warrants a careful discussion before starting.
  • Severe gastrointestinal disease, including gastroparesis.

Things to raise even if the form does not ask

  • Diabetes medication, particularly insulin or sulfonylureas — the combination can cause low blood sugar and doses often need adjusting.
  • Oral contraceptives — delayed stomach emptying can affect absorption. Ask specifically about this.
  • Any medication with a narrow therapeutic window, such as thyroid hormone, warfarin or anti-epileptics, where absorption timing matters.
  • A history of gallbladder disease. Rapid weight loss raises gallstone risk.
  • Diabetic retinopathy. Rapid improvement in blood sugar has been associated with worsening retinopathy.
  • Any planned surgery or procedure involving sedation. Delayed stomach emptying matters to anaesthetists, and they need to know.

Important. Tell any anaesthetist, endoscopist or surgeon that you are taking a GLP-1, well before the procedure. Delayed gastric emptying raises the risk of aspiration under sedation, and guidance on pausing the medication beforehand exists for exactly this reason.

Symptoms that mean stop and seek care

  • Severe, persistent abdominal pain, especially radiating to the back — possible pancreatitis.
  • Persistent vomiting, or inability to keep fluids down.
  • Swelling of the face, lips or throat, or difficulty breathing.
  • A lump or swelling in the neck, hoarseness, or trouble swallowing.
  • Sudden changes in vision.

This is not a complete list of risks or interactions. Read the information supplied with your medication, and if you are in any doubt, ask a pharmacist — they will answer this kind of question for free. In an emergency, call your local emergency number.

Programmes that take a proper history

Intake depth varies a great deal. Mochi and LifeMD run the most thorough processes among those we review, which slows sign-up and is the point.

Dispensed byProductPer monthScore
Coreage Rx
Best overall on true monthly cost
Compounded$1994.5
Trimi
Lowest flat price with named pharmacies
Compounded$1254.6
PlexusDx
Pharmacy transparency and genetic testing
Compounded$1894.4
Ozari Health
Lowest advertised semaglutide price
Compounded$1254.4
Fifty 410
Prepaid blocks with no subscription
Compounded$1334.2
Ivím Health
Unlimited clinician access
Compounded$1994

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