Management of Sea Sickness in Susceptible Flight Crews

Sea sickness may greatly impact the readiness of Service personnel deployed aboard naval vessels. Medications used in the treatment of sea sickness may have adverse effects, limiting their use as flight crew. Although the prevalence of sea sickness in flight crews remains unclear, individual susceptibility and high sea states are established risk factors. Literature review can guide optimized management strategies for this population.

The first author conducted a PubMed search using the terms "sea sickness" "flight crew" "scopolamine," "hyoscine," and "cinnarizine," identifying 15 articles of 350 matches, which addressed potential impact to flight performance. Analysis also included two historic reports about motion sickness maintained within the U.K. Army Aviation Centre's aeromedical archives in Middle Wallop, Hampshire. Both authors reviewed aeromedical policy for the International Civil Aviation Organization, U.K. Civil Aviation Authority, U.S. Federal Aviation Authority, the National Aeronautics Space Administration, U.S. Army, U.S. Navy, and U.S. Air Force.

Scopolamine, also known as hyoscine, has fewer operationally relevant side effects than cinnarizine or first-generation antihistamines. Although no aeromedical authorities endorse the unsupervised use of scopolamine, many will consider authorizing its temporary use following an initial assessment on the ground. Evidence supports the concomitant use of stimulant medication for augmenting antinausea effects and countering the potential sedative effects of scopolamine.

Scopolamine should be considered as a first-line medication for flight crews at risk of sea sickness but such use must be guided by the appropriate aeromedical authority, ideally in conjunction with a ground trial to evaluate individual response. The limited evidence to support concurrent use of stimulants must be weighed against the challenges of maintaining accountability of controlled substances in the operational environment.