ABSTRACT
One of the most serious types of poisoning, and one that appears to be increasing in frequency in both adults and children, is that due to cyclic antidepressants (1-3). This group of drugs comprises the monocyclic, bicyclic, tri cyclic, and tetracyclic compounds as well as the newer agents that inhibit 5-hydroxytryptamine (5-HT) (4). Most of the newer antidepressants are difficult to categorize according to structure and activity, and there are now numerous types of chemical structures as well as func tional differences among many of the antidepressants. In this chapter the term tricyclic refers to any of the cyclic compounds as well as the noncyclic triazobipyridine derivative trazodone (5-7). The newer selective inhibitors of serotonin uptake (SSUIs) are discussed sep arately within this chapter, but their toxicity profile is quite different (Table 16-1).