Theophylline toxicity: Difference between revisions
No edit summary |
|||
(10 intermediate revisions by 3 users not shown) | |||
Line 1: | Line 1: | ||
''See [[theophylline]] for general drug information'' | ''See [[theophylline]] for general drug information.'' | ||
==Background== | ==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 | *PO available as elixer and capsule (12 or 24-hour extended release) | ||
*IV as aminophylline | *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== | ==Clinical Features== | ||
*Cardiovascular | *Cardiovascular | ||
**[[Sinus Tachycardia]] | **[[Sinus Tachycardia]] | ||
**Atrial/Ventricular [[arrhythmias]] | **Atrial/Ventricular [[arrhythmias]] | ||
**[[Hypotension]] | **[[Hypotension]] (due to β2-mediated vasodilation) | ||
*Metabolic | *Metabolic | ||
**[[Hypokalemia]] | **[[Hypokalemia]] | ||
**[[Metabolic Acidosis]] | **[[Metabolic Acidosis]] | ||
**[[Hyperthermia]] | **[[Hyperthermia]] | ||
**[[Hyperglycemia]] | **[[Hyperglycemia]] | ||
*Neurologic | |||
**Tremor | |||
**Agitation | |||
**[[Seizure]] | |||
*GI | *GI | ||
**[[Nausea/Vomiting]] | **[[Nausea/Vomiting]] | ||
==Differential Diagnosis== | ==Differential Diagnosis== | ||
*[[Beta-2 agonist]] toxicity | |||
*[[Sympathomimetic toxicity]] | |||
*[[Iron toxicity]] | |||
*[[Salicylate toxicity]] | |||
==Evaluation== | ==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]] | *[[ECG]] | ||
* | *Metabolic panel | ||
*Lactic acid level | |||
*CK | *CK | ||
* | *Evaluate for co-ingestion | ||
==Management== | ==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]]) | *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]] | *[[Seizures]] | ||
**[[Lorazepam]] (Ativan) 1st line | **[[Lorazepam]] (Ativan) 1st line | ||
**Phenobarbital if [[lorazepam]] ineffective | **Phenobarbital if [[lorazepam]] ineffective | ||
**Phenytoin (Dilantin) contraindicated as increases seizure in animal studies | **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) | |||
*Dialysis | |||
**Indicated in [[seizures]], severe [[arrhythmias]] | |||
==Disposition== | ==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== | ==See Also== | ||
Line 71: | Line 68: | ||
==External Links== | ==External Links== | ||
==References== | ==References== | ||
<references/> | |||
[[Category:Toxicology]] | [[Category:Toxicology]] |
Latest revision as of 23:51, 15 November 2018
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[1]:
- 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
- Neurologic
- Tremor
- Agitation
- Seizure
- GI
Differential Diagnosis
Evaluation
- Theophylline level[2]
- 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[1]
- 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
- 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
External Links
References
- ↑ 1.0 1.1 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.
- ↑ 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.