Ver el código de «Theophylline toxicity»

''See [[theophylline]] for general drug information.''
==Background==
*Primarily used as a bronchodilator, however rarely used now due to better available options
*Also studied for treatment of [[Acute Mountain Sickness]] and [[Contrast-Induced Nephropathy]]
*PO available as elixer and capsule (12 or 24-hour extended release)
*IV as aminophylline (shorter acting than PO)
*Mechanism of action<ref name="Fisher">Fisher, J., & Graudins, A. (2015). Intermittent haemodialysis and sustained low-efficiency dialysis (SLED) for acute theophylline toxicity. Journal of medical toxicology : official journal of the American College of Medical Toxicology, 11(3), 359-63.</ref>:
**Release of endogenous catecholamines → β2 agonism → bronchodilation
**PDE inhibition → increases cAMP
**Adenosine antagonist

==Clinical Features==
*Cardiovascular
**[[Sinus Tachycardia]]
**Atrial/Ventricular [[arrhythmias]]
**[[Hypotension]] (due to β2-mediated vasodilation)
*Metabolic
**[[Hypokalemia]]
**[[Metabolic Acidosis]]
**[[Hyperthermia]]
**[[Hyperglycemia]]
*Neurologic
**Tremor
**Agitation
**[[Seizure]]
*GI
**[[Nausea/Vomiting]]

==Differential Diagnosis==
*[[Beta-2 agonist]] toxicity
*[[Sympathomimetic toxicity]]
*[[Iron toxicity]]
*[[Salicylate toxicity]]

==Evaluation==
*Theophylline level<ref name="Aggelopoulou">Aggelopoulou, E., Tzortzis, S., Tsiourantani, F., Agrios, I., & Lazaridis, K. (2018). Atrial Fibrillation and Shock: Unmasking Theophylline Toxicity. Medical principles and practice : international journal of the Kuwait University, Health Science Centre, 27(4), 387-391.</ref>
**10–20 μg/mL - Therapeutic
**20-80 μg/mL - Toxic level 
**80-100 μg/mL - Severe toxicity or death
*[[ECG]]
*Metabolic panel
*Lactic acid level
*CK
*Evaluate for co-ingestion

==Management==
*Supportive care is the mainstay of treatment
*Cardiovascular
**Norepinephrine (alpha-agonist) for hypotension resistant to IVF
**Refractory hypotension may respond to non-selective beta-blockers<ref name="Fisher" />
**Beta-blockers (esmolol preferred due to short half-life) for tachydysrhythmias
*GI decontamination ([[Multidose Activated Charcoal]], [[Whole Bowel Irrigation]])
**Consider in recent severe overdose
**Contraindications: unsecured airway, [[nausea]]/[[vomiting]], ileus, [[Bowel Obstruction]], or need for emergent endoscopy
*[[Seizures]]
**[[Lorazepam]] (Ativan) 1st line
**Phenobarbital if [[lorazepam]] ineffective
**Phenytoin (Dilantin) contraindicated as increases seizure in animal studies
*Dialysis or plasmapheresis
**Indicated in [[seizures]], severe [[arrhythmias]], hypotension, serum level >90 μg/mL (>40 μg/mL in chronic ingestion)

==Disposition==
*Almost all patients will require admission
*Can consider discharge with close followup (in conjunction with toxicology) if unintentional overdose, asymptomatic, and normal vital signs

==See Also==
*[[Toxicology (main)]]

==External Links==


==References==
<references/>

[[Category:Toxicology]]