Long term treatment with theophylline increases malonyl dialdehyde plasma concentrations.

As theophylline is known to stimulate lipolysis and lipid mobilisation, plasma concentrations of malonyl dialdehyde were studied in asthmatic patients being treated with sustained release theophylline. Malonyl dialdehyde was assessed as malonyl dialdehyde like material (MDA-LM) by the thiobarbituric acid assay. In a kinetic study (eight patients) plasma MDA-LM concentrations were found to be significantly higher after 30 than after eight days' treatment or before treatment, but not significantly different after 90 than after 30 days. In a comparative study (29 patients and 29 healthy volunteers) the mean plasma MDA-LM concentration was shown to be very significantly higher in the asthmatic group. The results are probably explained by an effect of theophylline on lipid peroxidation, and the effect of long term treatment on plasma MDA-LM merits further investigation.