BCG
vaccine appears to slightly increase the
half-life of
theophylline. Normally influenza
vaccines (whole-virion, split-virion and surface
antigen) do not interact with
theophylline, but raised
theophylline levels and
toxicity have been seen in occasional cases.
It seems possible that the occasional patient may develop some signs of
theophylline toxicity, especially if their
serum levels are already towards the top end of the therapeutic range, but most patients are unlikely to be affected.