The Dose Makes the Poison
Dosage is the amount of a medicine given. A sixteenth-century physician summed up toxicology in a single sentence about it.
Dosage is the amount and frequency of a medicine to be taken. Paracelsus stated the central principle of toxicology in the 1530s: everything is poison and nothing is without poison, and only the dose makes a thing not poisonous. Water, oxygen and table salt will all kill at sufficient quantity, and many poisons are medicines at low dose.
- The amount and schedule of medicine. *The correct dosage.*
- Dose — a single amount. *One dose daily.*
- To administer. *Dosed with antibiotics.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | dosage | Adjust the dosage. |
| Noun | dose | A single dose. |
| Verb | dose | Dose carefully. |
| Related | overdose | An accidental overdose. |
| Related | posology | The study of dosage. |
How it is used in a sentence
- The dosage was reduced.Amount and frequency.
- One dose every eight hours.A single administration.
- The dose makes the poison.Paracelsus.
Dosage terms
- Therapeutic dose — the amount producing the intended effect
- Toxic dose — the amount causing harm
- Therapeutic window — the gap between the two
- LD50 — the dose lethal to half a test population
- Loading dose — a larger initial amount to reach effective levels quickly
From French *dose*, from Greek *dosis*, a giving, from *didonai*, to give. The suffix *-age* forms a noun of quantity.
Dose or dosage?
A dose is one amount taken. Dosage is the whole regimen: how much, how often and for how long.
What is a therapeutic window?
The range between the dose that works and the dose that harms. A narrow window makes a drug difficult to use safely.