Engångsdoser

Engångsdoser, or single-dose regimens, are doses of a drug administered only once, in contrast to regimens that use repeated dosing. The term is used in pharmacology, clinical research, and medical practice to describe a one-off exposure and to distinguish it from maintenance or loading-dose strategies.

In research and clinical use, engångsdoser are common in early-phase clinical trials and pharmacokinetic studies, where the goal is to characterize absorption, distribution, metabolism, and excretion, as well as safety and tolerability, without the confounding effects of repeated dosing. They may also be used in certain therapeutic or diagnostic procedures where a single exposure is sufficient.

Pharmacokinetic data from a single-dose administration include metrics such as maximum concentration (Cmax), time to reach Cmax (Tmax), and the area under the concentration-time curve (AUC). These data help determine dosing intervals, the potential need for loading doses, and the overall exposure of the patient.

Advantages of engångsdoser include lower cumulative exposure and simplified monitoring, whereas limitations include the inability to maintain therapeutic levels over time and potentially higher peak-related adverse effects. For chronic conditions, repeated dosing regimens are typically required.

Safety considerations include patient selection, potential interactions, and monitoring for adverse effects after the single exposure. In clinical practice, the decision to use an engångsdose depends on the drug’s properties, the purpose of administration, and the patient’s condition.