| To obtain emergency consultation with a medical toxicologist, in the United States, call 1-800-222-1222 for the nearest regional poison control center. Contact information for poison control centers around the world is available at the WHO website and in the UpToDate topic on regional poison control centers (society guideline links). |
| Clinical features |
| Ingestion of sustained release oral preparations is most common |
Physical findings: - Vomiting
- Hypokalemia
- Hyperglycemia
- Metabolic acidosis
- Sinus tachycardia and other tachyarrhythmias (SVT, VT)
- Hypotension
- Seizures
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| Acutely poisoned patients are at high risk for seizures and arrhythmias if theophylline level ≥80 to 100 micrograms/mL (448 to 560 micromol/L) |
| Chronically poisoned patients may be relatively asymptomatic at presentation and are at high risk for seizures and arrhythmias if age ≤6 months or over 65 years of age and theophylline level ≥30 to 40 micrograms/mL (168 to 224 micromol/L) |
| Diagnostic evaluation |
| All symptomatic patients: |
- Emergency serum theophylline level (in patients with an acute overdose, repeat every 2 hours until peak level occurs)
- Serum electrolytes, calcium, and glucose
- Electrocardiogram
- Chest radiograph
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| Treatment |
| Supportive care |
Vomiting: - IV ondansetron 0.15 mg/kg, maximum dose 16 mg, obtain EKG prior to administration to screen for prolonged QTc
- IV famotidine 20 mg (pediatric dose 0.25 mg/kg up to maximum dose 20 mg)
- For vomiting refractory to ondansetron, high-dose IV metoclopramide 0.5 to 1 mg/kg, maximum single dose 50 mg (IV diphenhydramine 25 to 50 mg [pediatric dose 1 mg/kg], maximum total dose 50 mg may also be given to prevent a dystonic reaction)
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Seizures (for dosing, timing, and alternative medications for refractory seizures, refer to UpToDate content on convulsive status epilepticus): - First line: Benzodiazepines (eg, lorazepam, repeat once)
- Second line: Levetiracetam or phenobarbital. Avoid fosphenytoin or phenytoin.
- Refractory seizures: Midazolam infusion
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Arrhythmias: - Treat according to ACLS or PALS guidelines
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Hypotension: - First line: IV isotonic saline or lactated Ringer (20 mL/kg, maximum 1 L), up to 60 mL/kg (3 L) and, for SVT or VT, treatment of arrhythmias
- Second line: Options include one of the following:
- Phenylephrine continuous IV infusion – Initial dose 0.5 to 2 mcg/kg/minute (children 0.1 to 0.5 mcg/kg/minute), titrate to effect
- Norepinephrine continuous IV infusion – Initial dose 0.05 to 0.1 mcg/kg/minute, titrate to effect; or, in adults (estimated weight 80 kg), non-weight-based dosing 5 to 15 mcg/minute
- If hypotension is refractory to phenylephrine or norepinephrine, consult a medical toxicologist for advice on using a beta-adrenergic antagonist (eg, propranolol or esmolol)
- Avoid epinephrine and dobutamine
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| Gastrointestinal decontamination |
- Administer activated charcoal 1 g/kg up to 50 grams
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| Elimination enhancement and extracorporeal removal |
- For symptomatic patients with an acute theophylline overdose, perform elimination enhancement with MDAC 0.5 to 1 g/kg every 2 to 4 hours with cathartic (eg, sorbitol) no more than every third dose
- Perform high-efficiency hemodialysis (preferred) in patients with high risk for life-threatening toxicity based upon clinical symptoms (eg, seizures, refractory shock, or life-threatening arrhythmias), theophylline level, ability to perform elimination enhancement with MDAC, and whether the poisoning is acute or chronic. For specific indications, refer to UpToDate content on theophylline poisoning.
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