The 79-year-old birdwatcher and conservationist tweeted he had been suffering from "lithium toxicity". He wrote: "Just so you know, I have been very ill most of this summer. Lithium toxicity.

Common side effects of lithium include: The following signs could indicate toxicity and a need for medical evaluation: A number of studies have looked into ways to manage the side effects of lithium.

Discontinue if signs of neurologic toxicity occur with antipsychotics (eg, haloperidol, risperidone, thioridazine). Xanthines, acetazolamide, urea, alkalinizing agents may reduce serum lithium levels.

Discontinue if signs of neurologic toxicity occur with antipsychotics (eg, haloperidol, risperidone, thioridazine). Xanthines, acetazolamide, urea, alkalinizing agents may reduce serum lithium levels.