TABLE 2.

Synthetic drugs acting on the CNS and their possible limitation.

Therapeutic class	Pharmacological Use	Limitation/Possible side effect	Examples	References
Antidepressants	CNS stimulants; anticholinergic	Tricyclics may promote dry mouth, impaired vision, tachycardia, and cardiac arrythmias	Monoamine oxidase inhibitors and tricyclic antidepressants	(Walsh, 1979; Livingston and Livingston, 1996; Youdim et al., 2006)
Antipsychotics	Relieve anxiety and thought disturbances	These medications have the potential to induce drowsiness, hypothermia, hypotension, and lowering in seizure threshold.	Butyrophenones and phenothiazines	(Janssen, 1965; Martin et al., 1992)
Antiemetics	Relieve nausea and vomiting	Antihistamines are the only treatments that are recommended for divers to use in order to prevent motion sickness; nevertheless, the sleepiness generated by these medications might induce a reduction in cognitive ability.	Anticholinergics and antihistamines	Williams et al. (1988)
Anxiolytics	Relieve anxiety; depress CNS	Anxiolytic medications often produce sleepiness, lethargy, disorientation, and hypotension, all of which have the potential to be catastrophic in the water.	Benzodiazepines	(Groner-Strauss and Strauss, 1976; Greenblatt et al., 1983; Stewart, 2005)
CNS Stimulants	ncrease alertness; inhibit fatigue; suppress appetite; mood elevation	These may bring on symptoms such as exhilaration, increased perspiration, anxiety, and panic attacks.	Amphetamines	(Cheshire et al., 2001; Fleckenstein et al., 2007; Carvalho et al., 2012)
Hypnotics	Depress CNS and induce sleep	It may produce drowsiness, asthenia (weakness), headache, and aeuromuscular and skeletal weakness	Barbiturates	(Vermeeren, 2004; Charney et al., 2006)