Glossarium

The concept of a “Unit dose of a drug” is used in different scenarios related to drug use.

In this scenario, the “unit dose” is defined as the amount of medication given at a specific time (most common definition found on the web). For example, 250 mg in the morning, 10 mL (2 drops) in the morning, 1 pill after lunch, etc.

In this scenario, the unit dose is defined as the amount of medication given weight units (kilogram or pounds) per day. For example, 20 mg/kg*day. This is the standard working procedure to describe and compare drug doses in food animal veterinary medicine. The proposed dose, available on a body weight basis, is used by the health professional to prepare a dosage regimen to medicate the animal patient.

In this scenario, the unit dose is defined as the amount of medication added per weight unit of food to be distributed to a patient (ex: 600 mg/kg of feed, 600 g/tonne or 600 PPM).

In this scenario, the unit dose is defined as the amount of medication added per volume of water (liter or gallon) to be distributed to a patient.

DDD is a statistical measure of drug consumption developed by the World Health Organization (WHO) used to standardize the comparative usage of various drugs between themselves or between different healthcare environments independently of cost or drug and formulation. In this scenario, the “unit dose” is defined as the amount of medication given to a 70 kg adult human on a daily basis. The unit of a DDD measure differs from the unit of the DDDvet measure (mg/day versus mg/kg/day, respectively).

More details in the following website (ATC and DDD an international language for drug utilization research)

DDDvet is a statistical measure of drug consumption developed by the European countries and Canada to standardize the comparative usage of drugs (mainly antibiotics). In this scenario, the unit dose is defined as the amount of medication given to one kg of an animal on a daily basis. The unit of a DDDvet measure differs from the unit of the DDD measure (mg/kg/day versus mg/day, respectively).

More details in the following document : ESVAC 2016 « Defined daily doses for animals DDDvet) and defined course doses for animals (DCDvet) ».