Novartis has issued a medicine safety information letter limiting the maximum adult daily dose of their Tegretol suspension formulation to 1200mg/day (i.e. 60mL/day) to avoid possible exposure  to more than the permitted daily exposure (PDE) of ethylene glycol. Sorbitol is a potential source of ethylene glycol. Manufacturers are also required to ensure that all drug components conform to specified safety limits for ethylene and diethylene glycol.

Click here for the safety letter from the SAHPRA website. Click here for further information from the FDA.