Weight loss treatment glossary
54 terms you meet during treatment, each explained in one or two sentences. Every entry links to a guide with more detail.
B
- BMI
- Body mass index. Your weight in kilograms divided by your height in metres squared. Prescribers use BMI as one of the checks for treatment. BMI calculator
C
- Calorie deficit
- Eating fewer calories than your body uses. A deficit is needed for fat loss. Calorie calculator
- Check-in
- A short monthly form about your weight, side effects and how you feel. A prescriber reads each check-in before your next supply. How Aero Clinic works
- Cold chain
- Chilled packaging and fast delivery used to keep injection pens between 2 and 8 degrees C in transit. Delivery and packaging
D
- Dose step
- One level in a dose schedule. You stay on each step for a set minimum time before moving up. Mounjaro doses
E
- Efficacy estimand
- A trial result estimating the effect in people who stayed on the medicine. This figure is always higher than the result counting everyone. Clinical evidence
F
- Food noise
- Constant thoughts about food. Many people report less food noise on GLP-1 medicines. Emotional eating
- Foundayo
- The brand name for orforglipron tablets, taken once a day. Made by Eli Lilly. Read more
G
- Gallstones
- Small stones which form in the gallbladder. Rapid weight loss from any cause raises the risk. GLP-1 and gallstones
- Gastric emptying
- The speed at which food leaves your stomach. GLP-1 medicines slow gastric emptying, so you feel full for longer. What is a GLP-1 medicine?
- GIP
- Glucose-dependent insulinotropic polypeptide. A gut hormone involved in appetite and blood sugar. Mounjaro acts on GIP and GLP-1 receptors. How weight loss injections and pills work
- GLP-1
- Glucagon-like peptide-1. A gut hormone released after eating. GLP-1 tells your brain you are full and helps control blood sugar. What is a GLP-1 medicine?
- GLP-1 receptor agonist
- A medicine which acts on the same receptor as the GLP-1 hormone. Wegovy, the Wegovy pill and Foundayo belong to this group. What is a GLP-1 medicine?
- GMC
- General Medical Council. The regulator for doctors in the UK. Safety and regulation
- GPhC
- General Pharmaceutical Council. The regulator for pharmacies, pharmacists and pharmacy technicians in Great Britain. Safety and regulation
H
- Health check
- The online questionnaire about your health, medicines and weight. A prescriber reviews your answers before any prescription. How Aero Clinic works
- Hypoglycaemia
- Low blood sugar. The risk rises when a GLP-1 medicine is combined with insulin or a sulfonylurea. GLP-1 and type 2 diabetes
I
- Independent prescriber
- A pharmacist or nurse with an extra qualification allowing them to prescribe medicines. Clinical team
- Integrated care board
- An NHS body planning health services for a local area in England. Each board sets local access to NHS weight management. Weight loss treatment on the NHS
K
- KwikPen
- The multi-dose injection pen used for Mounjaro. One pen holds four weekly doses. Injection technique
L
- Lean mass
- Everything in your body other than fat, including muscle. Protein and resistance training help protect lean mass during weight loss. Muscle loss: prevention
- Licence
- Approval from the medicines regulator to market a medicine for a stated use. The licence sets the doses and who can take the medicine. Safety and regulation
- Liraglutide
- A daily GLP-1 injection. Nevolat is one brand. Nevolat
M
- Maintenance dose
- The dose you stay on once weight loss and side effects are in balance. Maintenance doses explained
- MHRA
- Medicines and Healthcare products Regulatory Agency. The UK regulator for medicines and medical devices. Safety and regulation
- Mounjaro
- The brand name for tirzepatide, a weekly injection. Made by Eli Lilly. Read more
N
- NICE
- National Institute for Health and Care Excellence. NICE writes guidance on which treatments the NHS in England should offer. Weight loss treatment on the NHS
O
- Off-licence use
- Using a medicine in a way the licence does not cover, such as a different dose gap. Only a prescriber can decide this. Maintenance doses explained
- Oral semaglutide
- Semaglutide in tablet form. The Wegovy pill is the version licensed for weight management. Read more
- Orforglipron
- The active ingredient in Foundayo. A GLP-1 medicine taken as a daily tablet with no food or water rules. Read more
- Orlistat
- A capsule taken with meals. Orlistat reduces the fat your gut absorbs. Orlistat
P
- Pancreatitis
- Inflammation of the pancreas. The main sign is severe stomach pain which does not ease. This needs emergency care. Urgent help
- Patient information leaflet
- The leaflet inside every medicine pack. The leaflet explains how to take the medicine and lists side effects. Weight loss medicine safety
- Placebo
- A dummy treatment with no active ingredient. Trials compare a medicine against placebo to measure the true effect. Clinical evidence
- Plateau
- A stretch of several weeks with no weight change despite steady habits. Breaking a plateau
- Prediabetes
- Blood sugar above the normal range but below the range for type 2 diabetes. GLP-1 and type 2 diabetes
- Prescriber
- A clinician with the legal right to prescribe medicines, such as a doctor or an independent prescriber. Clinical team
- Prescription only medicine
- A medicine you can get only with a prescription from a qualified prescriber. Often shortened to POM. Safety and regulation
R
- Randomised controlled trial
- A study where people are assigned by chance to a treatment or a comparison group. This design gives the most reliable evidence. Clinical evidence
S
- Semaglutide
- The active ingredient in Wegovy and the Wegovy pill. Made by Novo Nordisk. Read more
- Sharps bin
- A rigid container for used needles and pens. Injection technique
- SmPC
- Summary of product characteristics. The official document for clinicians describing how a medicine is used, with trial data and side effect rates. Clinical evidence
- Starter dose
- The first and lowest dose. The starter dose lets your body adjust before the dose rises. Your first month on Mounjaro
- Subcutaneous injection
- An injection into the fat layer under the skin of your stomach, thigh or upper arm. Injection technique
- Superintendent pharmacist
- The pharmacist accountable for the safe running of pharmacy services across a pharmacy company. Clinical team
T
- Tapering
- Lowering a dose in steps before stopping. Tapering off GLP-1 treatment
- Tirzepatide
- The active ingredient in Mounjaro. Tirzepatide acts on both GIP and GLP-1 receptors. Read more
- Titration
- Raising a dose in planned steps to limit side effects. Mounjaro doses
- Treatment-regimen estimand
- A trial result counting everyone who started, including people who stopped the medicine early. We quote this figure first on every page. Clinical evidence
- Type 2 diabetes
- A condition where blood sugar stays too high because insulin does not work well enough. GLP-1 and type 2 diabetes
W
- Wegovy
- The brand name for semaglutide for weight management. Available as a weekly pen and a daily tablet. Made by Novo Nordisk. Read more
- Weight regain
- Weight returning after treatment stops. A maintenance plan lowers the risk. Preventing weight regain
Y
- Yellow Card
- The MHRA scheme for reporting suspected side effects of medicines. Urgent help
Understand your treatment options
Explore the treatment guides and prepare your questions for a clinician. Aero’s prices and service details will be confirmed before booking opens.
Page information
- Summary
- Plain English definitions for 54 weight loss treatment terms, from BMI and GLP-1 to titration, maintenance dose and Yellow Card. Explore the full guide.
- Publisher
- Aero Clinic, operated by AERO HEALTHCARE LTD.
- Editorial update
- Clinical review
- Pending. An editorial update is not a clinical sign-off.
Cite as: Weight loss treatment glossary, Aero Clinic (https://www.cagri.co.uk), AERO HEALTHCARE LTD. https://www.cagri.co.uk/glossary. Editorial update: 4 November 2026. Clinical review pending.