Aminophylline
PHYLLOCONTIN
“A mean old Feline”
intravenous
tree → related to “tree-o-phylline” (also a CYP1A2 substrate)
What it isWater-soluble theophylline salt; acute bronchospasm.
Why this oneIt can be given intravenously when inhaled therapy is failing.
What limits itA narrow therapeutic index with levels required, and CYP1A2 makes it interaction-prone. Largely displaced by inhaled therapy.
FDA-approved for
- bronchospasm / asthma
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Acute bronchodilation (asthma/COPD) | Adult, non-smoking | Loading 5.7 mg/kg IV over 30 min (ideal body weight) | Maintenance infusion 0.5 mg/kg/hr | Titrate to serum theophylline 10–20 mcg/mL |
| Acute bronchodilation | Peds 1–9 yr | Loading 5.7 mg/kg IV | Infusion 1.0 mg/kg/hr | Serum theophylline 10–20 mcg/mL |
Renal Undefined
Hepatic In liver dysfunction (also cor pulmonale, cardiac decompensation, or clearance-reducing drugs), keep initial infusion ≤21 mg/hr (as aminophylline) unless serum levels are monitored.
Each 1 mg/kg (IBW) of theophylline raises serum concentration ~2 mcg/mL; aminophylline = theophylline / 0.8.
Instructions
- Individualize by serum theophylline concentration (target 10 mcg/mL initially).
- Do not give a loading dose if theophylline was taken in the previous 24 h without first checking a level.
- Do not mix in a syringe with other drugs—add separately to the IV solution.
- Avoid admixture with alkali-labile drugs (epinephrine, norepinephrine, isoproterenol, penicillin G potassium).
Available strengths
- inj 25 mg/mL
Cautions
- Caffeine-like effects (nausea, vomiting, headache, insomnia) usually mild at <20 mcg/mL
- Serious toxicity (arrhythmias, seizures, can be lethal) at >20 mcg/mL
- Ethylenediamine component can cause allergic skin reactions/contact dermatitis
Adverse reactions
- Nausea
- Vomiting
- Headache
- Insomnia
- Diarrhea
- Irritability/restlessness
- Fine skeletal muscle tremor
- Transient diuresis; at high levels arrhythmias and seizures
Pregnancy Undefined
Lactation Undefined
Cost
| Strength | #/mo | generic $/unit | CostPlus | |
|---|---|---|---|---|
| 25 mg/mL | inj | per unit | not offered |
NO BOXED WARNINGS
Principal riskA narrow therapeutic index with levels required, and CYP1A2 makes it interaction-prone
Classes and tags
Clinical profile
Open Aminophylline in the interactive console ↗
Memory aids: interaction avatars
