Oral toxicity of polyethylene glycol (PEG 200) in monkeys and rats

Polyethylene glycols, particularly those with low molecular weights, are considered to be relatively non-toxic. Polyethylene glycol (PEG 200) was administered orally to Cynomolgus monkeys (Macaca fascicularis) and rats (Sprague-Dawley origin) for a 13-week period at dosage levels of 2 to 4 ml/kg (monkeys) and 2.5 to 5.0 ml/kg/day (rats). Pathological lesions were encountered only in monkeys and these consisted of intratubular deposition of small numbers of oxalate crystals in the renal cortex. These lesions were not associated with other clinical or pathological findings.