The biological tests carried out on pharmaceutical aerosols are similar to tests performed on non-aerosol preparations. Basically they are tested for their therapeutic efficacy and toxicity.

Therapeutic efficacy—the inhalation aerosols or MDIs are tested for their dose uniformity and particle size distribution along with the pharmacokinetic and pharmacodynamic studies. Topical aerosols are applied to the test area and absorption of therapeutic ingredients is determined.

Toxicity testing should include both topical and inhalation effects. Aerosols applied topically may be irritating to the affected area and/or may cause chilling effect. Thermistor probes attached to recording thermometers have been used to indicate the change in skin temperature when an aerosol is sprayed on the skin for a given period of time. Determination of inhalation toxicity is accomplished by exposing test animals to vapors sprayed from an aerosol container.