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Poisoning monographs

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wikitox:2.1.11.4.6_xanthines

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Xanthines

There are three main xanthine derivatives. Theophylline and aminophylline are methylxanthines once widely used for the treatment of asthma, but now less commonly so. Caffeine is a trimethylxanthine closely related to theophylline. And theobromine, which is a plant extract.

The exact mechanism of toxicity is not known.

Theophylline

  • inhibits phosphodiesterase at high levels, increasing intracellular cyclic adenosine monophosphate (cAMP).
  • releases endogenous catecholamines
  • stimulates beta-adrenergic receptors.
  • And is an antagonist of adenosine receptors.

Caffeine

  • acts primarily through inhibition of the adenosine receptor.
  • In addition, with overdose there is beta-1 and beta-2 adrenergic stimulation secondary to release of endogenous catecholamines.

REFERENCES

Shannon M, Amitai Y, Lovejoy FH Jr. Multiple dose activated charcoal for theophylline poisoning in young infants. Pediatrics 1987;80(3):368-70 PMID3627887
Henderson A, Wright DM, Pond SM. Management of theophylline overdose patients in the intensive care unit. Anaesth Intensive Care 1992;20(1):56-62 PMID1609943

/home/wikitoxo/public_html/data/pages/wikitox/2.1.11.4.6_xanthines.txt · Last modified: 2018/09/01 09:00 (external edit)