What does it indicate if a drug has a long half-life?

A long half-life of a drug indicates that it takes longer for the drug's concentration in the body to decrease by half. Consequently, this lengthened duration impacts the time it takes to reach steady state, which is the point at which the drug's intake and elimination rates are balanced. When a drug has a long half-life, it will take more doses over time to achieve this equilibrium compared to drugs with shorter half-lives.

While some might think that a long half-life means that the drug should be administered more frequently—this is not the case; in fact, it often leads to less frequent dosing. The notion that it can be eliminated quickly from the body is contrary to what a long half-life suggests, as it implies a slower elimination process. Lastly, having a long half-life does not directly correlate to the drug’s potency; potency refers to the drug's effectiveness at producing a response at a given dose, rather than its duration in the body.