Am I Eligible?
Most weight loss drugs require a BMI of 30 or higher, or 27+ with qualifying health conditions. A doctor makes the final decision.
Quick read · 4 min
- •Most obesity drugs are prescribed if your BMI is 30 or higher
- •If your BMI is 27–29.9 AND you have conditions like diabetes or high blood pressure, you may also qualify
- •A doctor decides — not a website. This page helps you understand the general criteria.
- •BMI isn't perfect — it doesn't account for muscle mass or body type
Based on clinical trials · No rankings · Every claim linked to source
Last reviewed: March 2026
Check your BMI
Enter your height and weight to see your BMI and whether you would likely meet the standard criteria. This is a guide only — a doctor makes the final decision.
BMI Calculator
Standard FDA eligibility criteria
Classified as obesity. Eligible for FDA-approved weight loss medications regardless of whether other health conditions are present.
Classified as overweight with a weight-related health condition (like type 2 diabetes, high blood pressure, or sleep apnoea). Qualifying conditions include:
- ✓Type 2 diabetes
- ✓High blood pressure (hypertension)
- ✓High cholesterol (dyslipidaemia)
- ✓Obstructive sleep apnoea
- ✓Cardiovascular disease
Source: FDA approved indications + WHO GLP-1 guideline 2024 [1]
Reasons your doctor might say no
These conditions may prevent the use of certain or all weight loss medications. Your doctor will assess these individually.
Personal or family history of this rare thyroid cancer. FDA black box warning — GLP-1 receptors are found in thyroid cells. Animal studies showed tumour risk, though human risk is not established.
Multiple Endocrine Neoplasia type 2 — a rare inherited condition involving a genetic tendency to develop thyroid and other endocrine tumours.
Phentermine/topiramate causes cleft palate and other birth defects — absolutely cannot be used. GLP-1s are not approved for use in pregnancy.
Naltrexone blocks opioid receptors — cannot be used if you are taking opioids, as it will cause immediate withdrawal.
Bupropion lowers the seizure threshold — cannot be used in people with a history of seizures.
Phentermine is a stimulant — not suitable in narrow-angle glaucoma or overactive thyroid (hyperthyroidism).
BMI isn't perfect
BMI is used because it is standardised and easy to measure — not because it perfectly predicts individual health risk.
- ⚠Does not distinguish fat from muscle — a very muscular person may exceed the threshold without significant body fat.
- ⚠Some Asian populations have metabolic risk at lower BMI thresholds — some guidelines use ≥25 or ≥27 with health conditions.
- ⚠Does not capture where fat is stored — belly fat carries higher health risk than fat under the skin.
Who makes the decision?
A prescribing doctor or obesity medicine specialist. The criteria above are the general FDA-approved thresholds — individual decisions may involve additional factors including overall health, other medications, preference, and cost.