Thiazolidinediones

Thiazolidinediones (rosiglitazone, pioglitazone) are PPAR-γ agonists which act to reduce insulin resistance. Weight gain and peripheral oedema are among the commoner side effects of these drugs. Hepato-toxicity is rare, however, due to the cases of fatal hepatic failure which led to withdrawal of the first thiazolidinedione troglitazone, LFTs should be monitored before therapy starts then 2-monthly for a year and intermittently thereafter. Long-term benefit has not yet been demonstrated with these agents. NICE guidelines suggest that these drugs are recommended for patients unable to take metformin and sulphonylurea combination therapy or as a third line agent after failure of an adequate trial of metformin and sulphonylurea combination therapy as an alternative to insulin. They are not licensed in the UK as a first line agent.