II. Precautions

  1. Theophylline is listed here for completeness, not for recommended use
  2. In the developed world, Theophylline and its adverse effects are largely supplanted by better agents
    1. Limited roles may be found in refractory cases under specialty care, and in underdeveloped world regions

III. Indications

  1. Limited utility where standard of care Asthma Management is available

IV. Preparations: Methylxanthines

  1. Aminophylline
  2. Caffeine
  3. Pentoxifylline (Trental)
  4. Theophylline

V. Mechanism

  1. Xanthines are isolated from plants Camellia sinensis and Coffea arabica
  2. Activity: Xanthines and Methylxanthines in general
    1. Xanthines inhibit phosphodiesterase and Prostaglandin production
    2. Moderate cellular Calcium
    3. Block Adenosine
  3. Effects: Theophylline
    1. Bronchial Smooth Muscle relaxation (high doses of Theophylline)
    2. Peripheral vasodilation (not central)
    3. CNS and cardiac stimulant
    4. Diuretic
    5. Anti-inflammatory (at low doses of Theophylline)

VI. Dosing

  1. Theophylline 150 to 300 mg twice daily

VII. Pharmacokinetics: Oral Theophylline

  1. Half-Life: 8.5 hours in adults (3.5 hours in children)

VIII. Adverse Effects

  1. Serum Theophylline Level <20 mg/L
    1. Headache
    2. Insomnia
    3. Nausea
    4. Vomiting
  2. Serum Theophylline Level >20 mg/L
    1. Arrhythmias
    2. Seizures

IX. Drug Interactions

  1. Agents that increase Theophylline serum concentrations
    1. Alcohol
    2. Ciprofloxacin
    3. Diltiazem
    4. Erythromycin
    5. Oral Contraceptives
    6. Propranolol (very strong effect, doubles the Theophylline concentration)
    7. Verapamil
  2. Agents that decrease Theophylline serum concentrations
    1. Phenytoin (Dilantin)

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Related Studies

Cost: Medications

theophylline (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
THEOPHYLLINE ER 300 MG TAB Generic $2.38 each
THEOPHYLLINE ER 400 MG TABLET Generic $0.64 each
THEOPHYLLINE ER 600 MG TABLET Generic $0.96 each