Paraquat is a common human toxicant and accounts for 20 deaths per million persons in the world. Paraquat usually cause multiple organ dysfunction syndrome, including liver, kidney, lung and heart dysfunction. Besides, pituitary insufficiency also occurs on those patients with paraquat poisoning, which leads to multiple endocrine gland dysfunction, involving adrenal gland, thyroid and sex gland.

As a result, the investigators decide to initiate the clinical trial to find whether thyroid replacement therapy can furtherly reduce the mortality, and improve patients long-term prognosis.

Paraquat is a common human toxicant and accounts for 20 deaths per million persons in the world. Its accidental or deliberate ingestion is associated with a high mortality rate ranging from 40% to 70%. Paraquat usually cause multiple organ dysfunction syndrome, including liver, kidney, lung and heart dysfunction. Besides, pituitary insufficiency also occurs on those patients with paraquat poisoning, which leads to multiple endocrine gland dysfunction, involving adrenal gland, thyroid and sex gland. Nowadays, steroids, as a hormone replacement therapy, is one of most important drugs for paraquat poisoning, and it has decreased patients' mortality greatly since using it. However, the clinicians have not paid enough attention to thyroid replacement therapy, as thyroid dysfunction is also the key pathophysiological course when paraquat poisoning occurs.

As a result, the investigators decide to initiate the clinical trial to find whether thyroid replacement therapy can furtherly reduce the mortality, and improve patients long-term prognosis.

Inclusion Criteria:

• all the patients who are diagnosed by paraquat poisoning

Exclusion Criteria:

• patients who can not cooperate with the trial; patients who would not like to join in the trial.