Pharmacotherapeutics is an important element of space medicine practice. Assessing health risks, developing countermeasures, selecting relevant supplies for medical kits and providing appropriate training for crew members on the use of medical kits prior to the mission start are all major contributors of mission success. In this chapter, the standards applicable to clinical pharmacy practice are discussed, and best practices recommended. A review of existing evidence on the incidence and management of clinical conditions that have occurred during space flight is presented along with results of research conducted of drugs under the influence of microgravity. Ground-based models, such as bed-rest and animal surrogate studies, supplement and validate clinical observations from space missions. Space flight is associated with morphological and profound physiological changes, including alterations in fluid, electrolytes, and gastrointestinal function capable of affecting the pharmacokinetics—primarily after oral administration of medications. Exposure to the space environment, particularly radiation, can also shorten the shelf life of many chemical preparations, potentially affecting their efficacy, altering their bioavailability. Special packaging, radiation insulation of the medical storage area, and periodic return of samples to determine pharmacologic activity of medications is possible in Low Earth Orbit, such as the International Space Station, which offers a unique test-bed environment. Information on the absorption, distribution, metabolism, and excretion of major drug categories in the space microgravity environment is incomplete. Since research evidence on pharmacotherapeutics in space is sparse, clinical practitioners rely primarily on observational and anecdotal evidence compiled from individual crew opinions gathered from prior missions
