Cmax (pharmacology)

Cmax is a term used in pharmacology to denote the maximum (or peak) serum concentration that a drug achieves in a specified compartment or test area of the body after the drug has been administratively dosed and prior to the administration of a second dose.

Overview[edit | edit source]

Cmax is a key factor in determining the efficacy and safety of a drug. It is used in both the design and analysis of clinical trials, and in the routine monitoring of patients on certain types of medication. The Cmax of a drug is reached when the rate of absorption equals the rate of elimination. After this point, the drug concentration begins to decrease.

Measurement[edit | edit source]

Cmax is typically measured in micrograms per milliliter (µg/mL). It is determined by drawing a series of blood samples following the administration of a drug and analyzing these samples to determine the drug concentration at various times. The maximum concentration observed is the Cmax.

Factors Influencing Cmax[edit | edit source]

Several factors can influence the Cmax of a drug, including the dose, the rate of absorption, the rate of elimination, and individual patient factors such as age, sex, body weight, and organ function.

Clinical Significance[edit | edit source]

The Cmax of a drug can have important clinical implications. For example, a drug with a high Cmax may produce more pronounced effects, but may also be more likely to cause side effects. Conversely, a drug with a low Cmax may be less effective, but also less likely to cause side effects.