Use ideal body weight for obese patients
Children:
6 weeks to 6 months: 0.5 mg/kg/hour
6 months to 1 year: 0.6-0.7 mg/kg/hour
Children >1 year and Adults:
Treatment of acute bronchospasm: I.V.: Loading dose (in patients not
currently receiving aminophylline or theophylline): 6 mg/kg (based on
aminophylline) given I.V. over 20-30 minutes; administration rate should not
exceed 25 mg/minute (aminophylline).
After the loading dose, refer to the following for approximate I.V.
theophylline dosages (equivalent hydrous aminophylline dosage indicated in
parentheses):
Infants 6 weeks to 6 months:
0.5 mg/kg/hour for next 12 hours
Children 6 months to 1 year:
0.6-0.7 mg/kg/hour for next 12 hours
Children 1-9 years:
0.95 mg/kg/hour (1.2 mg/kg/hour) for next 12 hours; 0.79 mg/kg/hour (1
mg/kg/hour) dosage after 12 hours
Children 9-16 years and young adult smokers:
0.79 mg/kg/hour (1 mg/kg/hour) for next 12 hours; 0.63 mg/kg/hour (0.8
mg/kg/hour) dosage after 12 hours
Healthy, nonsmoking adults:
0.55 mg/kg/hour (0.7 mg/kg/hour) for next 12 hours; 0.39 mg/kg/hour (0.5
mg/kg/hour) dosage after 12 hours
Older patients and patients with cor pulmonale:
0.47 mg/kg/hour (0.6 mg/kg/hour) for next 12 hours; 0.24 mg/kg/hour (0.3
mg/kg/hour) dosage after 12 hours
Patients with congestive heart failure or liver failure:
0.39 mg/kg/hour (0.5 mg/kg/hour) for next 12 hours; 0.08-0.16 mg/kg/hour
(0.1-0.2 mg/kg/hour) dosage after 12 hours
Approximate I.V. maintenance dosages are based upon continuous
infusions; bolus dosing (often used in children <6 months of age) may be
determined by multiplying the hourly infusion rate by 24 hours and dividing by
the desired number of doses/day. See the following:
Maintenance dose for acute symptoms:
Premature infant or newborn to 6 weeks (for apnea/bradycardia):
Oral theophylline dose: 4 mg/kg/day
I.V. aminophylline dose: 5 mg/kg/day
6 weeks to 6 months:
Oral theophylline dose: 10 mg/kg/day
I.V. aminophylline dose: 12 mg/kg/day or continuous I.V. infusion*
Infants 6 months to 1 year:
Oral theophylline dose: 12-18 mg/kg/day
I.V. aminophylline dose: 15 mg/kg/day or continuous I.V. infusion*
Children 1-9 years:
Oral theophylline dose: 20-24 mg/kg/day
I.V. aminophylline dose: 1 mg/kg/hour
Children 9-12 years, and adolescent daily smokers of cigarettes or marijuana,
and otherwise healthy adult smokers <50 years:
Oral theophylline dose: 16 mg/kg/day
I.V. aminophylline dose: 0.9 mg/kg/hour
Adolescents 12-16 years (nonsmokers):
Oral theophylline dose: 13 mg/kg/day
I.V. aminophylline dose: 0.7 mg/kg/hour
Otherwise healthy nonsmoking adults (including elderly patients):
Oral theophylline dose: 10 mg/kg/day (not to exceed 900 mg/day)
I.V. aminophylline dose: 0.5 mg/kg/hour
Cardiac decompensation, cor pulmonale and/or liver dysfunction
Oral theophylline dose: 5 mg/kg/day (not to exceed 400 mg/day)
I.V. aminophylline dose: 0.25 mg/kg/hour I.V.
*For continuous I.V. infusion, divide total daily dose by 24 = mg/kg/hour.
Dosage should be adjusted according to serum level measurements during the
first 12- to 24-hour period. See the following:
Theophylline level within normal limits:
10-20 mcg/mL: Maintain dosage if tolerated.
Recheck serum theophylline concentration at 6- to 12-month intervals.*
Theophylline level too high:
20-25 mcg/mL: Decrease doses by about 10%.
Recheck serum theophylline concentration after 3 days and then at 6- to
12-month intervals.*
25-30 mcg/mL: Skip next dose and decrease subsequent doses by about 25%.
Recheck serum theophylline.
>30 mcg/mL: Skip next 2 doses and decrease subsequent doses by 50%.
Recheck serum theophylline.
Theophylline level too low:
7.5-10 mcg/mL: Increase dose by about 25%**
Recheck serum theophylline concentration after 3 days and then at 6- to
12-month intervals.*
5-7.5 mcg/mL: Increase dose by about 25% to the nearest dose increment ** and
recheck serum theophylline for guidance in further dosage adjustment (another
increase will probably be needed, but this provides a safety check).
*Finer adjustments in dosage may be needed for some patients.
**Dividing the daily dose into 3 doses administered at 8-hour intervals may
be indicated if symptoms occur repeatedly at the end of a dosing interval.
(From Weinberger M and Hendeles L,
"Practical Guide to Using Theophylline," J Resp Dis, 1981, 2:12-27.)
Oral theophylline: Initial dosage recommendation: Loading dose (to
achieve a serum level of about 10 mcg/mL; loading doses should be given using a
rapidly absorbed oral product not a sustained release product):
If no theophylline has been administered in the previous 24 hours: 4-6 mg/kg
theophylline
If theophylline has been administered in the previous 24 hours: administer
1/2
loading dose or 2-3 mg/kg theophylline can be given in emergencies when serum
levels are not available
On the average, for every 1 mg/kg theophylline given, blood levels will rise
2 mcg/mL
Ideally, defer the loading dose if a serum theophylline concentration can be
obtained rapidly. However, if this is not possible, exercise clinical judgment.
If the patient is not experiencing theophylline toxicity, this is unlikely to
result in dangerous adverse effects.
Oral theophylline dosage for bronchial asthma (by age):
<1 year:
Initial 3 days and second 3 days: 0.2 x (age in weeks) + 5 = mg/kg/24 hours
of theophylline
Steady-state maintenance: 0.3 x (age in weeks) + 8 = mg/kg/24 hours of
theophylline
1-9 years:
Initial 3 days: 16 mg/kg/24 hours of theophylline, up to a maximum of 400
mg/24 hours
Second 3 days: 20 mg/kg/24 hours of theophylline
Steady-state maintenance: 22 mg/kg/24 hours of theophylline
9-12 years:
Initial 3 days: 16 mg/kg/24 hours of theophylline, up to a maximum of 400
mg/24 hours
Second 3 days: 16 mg/kg/24 hours of theophylline, up to a maximum of 600
mg/24 hours
Steady-state maintenance: 20 mg/kg/24 hours of theophylline, up to a maximum
of 800 mg/24 hours
12-16 years:
Initial 3 days: 16 mg/kg/24 hours of theophylline, up to a maximum of 400
mg/24 hours
Second 3 days: 16 mg/kg/24 hours of theophylline, up to a maximum of 600
mg/24 hours
Steady-state maintenance: 18 mg/kg/24 hours of theophylline, up to a maximum
of 900 mg/24 hours
Adults:
Initial 3 days: 400 mg/24 hours
Second 3 days: 600 mg/24 hours
Steady-state maintenance: 900 mg/24 hours
Increasing dose: The dosage may be increased in approximately 25%
increments at 2- to 3-day intervals so long as the drug is tolerated or until
the maximum dose is reached
Maintenance dose: In children and healthy adults, a slow-release
product can be used; the total daily dose can be divided every 8-12 hours