loading dose
An initial higher dose given to rapidly achieve therapeutic drug levels.
Full Definition
A loading dose is a larger initial dose of medication administered to quickly reach steady-state plasma concentrations, particularly for drugs with long half-lives. This pharmacokinetic strategy is used when rapid therapeutic effects are needed and waiting for gradual accumulation would delay treatment benefits. In psychopharmacology, loading doses are sometimes used with mood stabilizers like lithium or valproate in acute settings. The loading dose is calculated based on the drug's volume of distribution and desired plasma concentration, followed by maintenance dosing to sustain therapeutic levels.
Usage
Usage note: Always hyphenate when used as a compound modifier; distinguish from maintenance dosing in treatment protocols.
In Context
- "A loading dose of valproate was administered to rapidly achieve antimanic serum levels in the emergency department." — Emergency psychiatry protocol
- "The loading dose strategy allows for immediate therapeutic benefits rather than waiting weeks for steady-state accumulation." — Clinical pharmacokinetics guide