31 terms
A
- Adverse reaction
An unwanted effect thought to be caused by a medicine. It can be mild, like nausea, or serious.
Drug labels list adverse reactions seen in clinical trials, usually next to how often the same thing happened in people taking a placebo.
B
- Bariatric surgery
Weight-loss surgery that changes the stomach or digestive system, such as a sleeve gastrectomy or a gastric bypass.
- BMI
Body mass index: a number worked out from your height and weight. It is a rough screening measure, not a direct measure of body fat.
BMI can be misleading for very muscular people. It is still the measure most drug trials and prescribing rules use to decide who a treatment is for.
- Boxed warning
The most serious kind of warning on a US drug label, printed inside a box at the top.
Also called a black box warning. It does not mean the risk is common. It means the FDA wants doctors and patients to see it clearly.
C
- Cohort study
A study that follows a group of people over time and records what happens, without randomly deciding who gets which treatment.
Cohort studies are useful, but the groups being compared may differ in ways other than the treatment, so they are weaker evidence than a randomised controlled trial.
- Comorbidity
Another health condition someone has at the same time, such as high blood pressure alongside obesity.
- Compounded
Made by a pharmacy rather than by the drug's manufacturer. Compounded versions are not FDA-approved products.
The FDA's rules on when pharmacies may make copies of a brand-name drug depend partly on whether that drug is in shortage.
- Contraindication
A situation in which a drug's label says the drug should not be used, such as a particular health condition.
Contraindications are listed on the drug's official label. They are different from warnings and precautions, which call for extra care rather than ruling the drug out.
D
- Discontinuation rate
The share of people in a study who stopped taking the treatment before the study ended, for any reason.
Trials usually also report how many people stopped because of side effects. That smaller number is the one most side-effect pages quote.
- Drug interaction
When one medicine changes how another medicine works, or how strongly it acts.
- Drug label
The official document approved by a regulator for a medicine. It says what the medicine is for, how to take it and what its risks are.
In the US this is the FDA label, also called the prescribing information. It is the main source this site links to for doses, warnings and approved uses.
- Drug shortage
A period when the supply of a medicine does not meet demand, so it can be hard to get.
The FDA keeps an official shortage list. Whether a drug is on it affects whether pharmacies may compound copies of it.
E
- Eligibility criteria
The requirements, such as BMI or health history, that decide who a treatment is approved for or who can join a trial.
- Estimand
The exact question a trial's headline number answers. For example: results for everyone who started, or only for people who kept taking the drug.
The 'treatment-regimen' estimand counts everyone who started, even people who stopped early. The 'efficacy' estimand counts people who kept taking the drug as planned. One trial can report both, and they give different numbers.
G
- GIP
A gut hormone that, like GLP-1, is involved in appetite and blood sugar. Some newer drugs act like both hormones at once.
GIP stands for glucose-dependent insulinotropic polypeptide. Tirzepatide acts on both GIP and GLP-1 receptors, which is why it is called a dual agonist.
- GLP-1
A hormone your gut releases after eating. It helps signal fullness and slows how fast your stomach empties. Many weight-loss drugs act like it.
GLP-1 stands for glucagon-like peptide-1. Drugs that act like it are called GLP-1 receptor agonists.
H
- Half-life
The time it takes for the amount of a drug in your body to fall by half.
A long half-life is one reason some drugs only need to be taken once a week.
I
- Injection site
The place on the body where an injectable drug is given, such as the stomach area, thigh or upper arm.
L
- Lean mass
Everything in your body that isn't fat: mostly muscle, plus organs, bone and water.
Some of the weight lost on any diet or drug is lean mass as well as fat. This is why strength exercise is often recommended during treatment.
- List price
The full price a manufacturer sets before any discount, savings programme or insurance.
Many people pay less than list price, through insurance or a manufacturer's self-pay price.
M
- Maintenance dose
The dose someone stays on long term, once the step-by-step increases are finished.
- Missed dose
A planned dose that was forgotten or skipped. What to do next depends on the drug and how late it is; each label gives its own rule.
P
- Phase 3
The large, late stage of clinical trials that usually comes before a company asks regulators to approve a drug.
Drugs usually go through Phase 1 (safety, in small groups), Phase 2 (finding the right dose) and Phase 3 (large trials, often in hundreds or thousands of people).
- Placebo
A dummy treatment with no active drug. One group in a trial gets it, so researchers can see what the real drug added.
In weight-loss trials the placebo group often still loses some weight, because everyone in the trial usually gets diet and exercise advice.
- Plateau
A stretch of time when weight loss slows or stops, even while still taking a treatment as prescribed.
Plateaus are common during weight loss and are not necessarily a sign that a treatment has stopped working.
R
- Randomised controlled trial
A study where people are put into groups by chance: one gets the treatment, another gets a comparison, often a placebo.
Assigning groups by chance means the groups start out alike, so differences at the end are more likely to come from the treatment. It is generally seen as among the strongest kinds of evidence.
S
- Self-pay
Paying for a medicine yourself rather than through insurance, often at a price set by the manufacturer's own programme.
- Sham-controlled trial
A trial of a device or procedure where the comparison group gets a pretend version, much as a drug trial uses a placebo.
- Starting dose
The low dose used at the very start of treatment, before it is stepped up.
T
- Titration
Raising a drug's dose in steps over several weeks, instead of starting at the full dose, so the body has time to adjust.
Each drug's FDA label sets out its own schedule. Some labels allow staying on a dose for longer if side effects are hard to tolerate; that is a decision for the prescriber.
W
- Weight regain
Weight that comes back after it was lost, for example after stopping a treatment.
Written and maintained by one person · Built with agentic AI tools · Every number checked against the cited trial · Not medical advice
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