“…In the past several penicillins including ampicillin (Keating et al, 1974), streptomycin (Hartmann and Augevine, 1956), the tetracyclines, chloramphenicol (Newman, 1956) and erythromycin (Hardaway and McKay, I959), novobiocin (Baden, 1957) and neomycin (Groll et al, 1970) have been implicated (Altemeier et al, 1963). It is possible that antibiotics may interact with local factors within the intestine, such as ischaemia (Markley et al, 1958), thrombosis (McKay et al, 1955, changes following intestinal surgery (Petter et al, 1954;Hale and Cosgriff, 1957) and obstruction (Petter et al, 1954;Menaker and Van Hagen, 1959).…”