Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
FORADIL vs AEROLATE SR
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Formoterol is a long-acting beta2-adrenergic receptor agonist (LABA) that relaxes bronchial smooth muscle by increasing intracellular cyclic AMP.
AEROLATE SR is a sustained-release formulation of theophylline, a methylxanthine bronchodilator. It acts by inhibiting phosphodiesterase (PDE) isoenzymes, leading to increased intracellular cyclic AMP (c AMP) levels. This results in relaxation of bronchial smooth muscle and suppression of the response of airways to stimuli. Theophylline also has anti-inflammatory effects, including inhibition of late-phase allergen-induced responses and reduction of eosinophil infiltration.
Long-term maintenance treatment of asthma,Prevention of exercise-induced bronchospasm,Maintenance treatment of chronic obstructive pulmonary disease (COPD)
Treatment of symptoms and reversible airway obstruction associated with chronic asthma,Chronic obstructive pulmonary disease (COPD),Apnea of prematurity (off-label)
Inhalation: 12 mcg twice daily (every 12 hours) via Foradil Aerolizer.
400-800 mcg inhaled twice daily. For acute bronchospasm, 200-400 mcg as needed.
Terminal half-life: 7-10 hours. Steady-state achieved within 3-5 days; clinical context: allows twice-daily dosing for bronchodilation.
Terminal elimination half-life 12 hours (range 10–15 h) in adults; prolonged in hepatic impairment (up to 24 h) and elderly.
Metabolized primarily by hepatic glucuronidation and to a lesser extent by CYP2D6, CYP2C19, and CYP2C9.
Primarily hepatic via cytochrome P450 enzymes (CYP1A2, CYP2E1, and CYP3A4). Theophylline is metabolized to 1,3-dimethyluric acid, 1-methyluric acid, and 3-methylxanthine.
Renal (60% as unchanged drug and metabolites) and fecal (40% as metabolites).
Renal: 60% as unchanged drug; biliary/fecal: 30% as metabolites; 10% as unchanged in feces.
61% bound to plasma proteins, primarily albumin.
55–65% bound to plasma proteins, primarily albumin.
6.0 L/kg (extensive tissue distribution, indicating high penetration into lungs and peripheral tissues).
0.4–0.6 L/kg, indicating distribution into total body water.
Inhalation: ~30% (systemic absorption from lungs; oral bioavailability negligible due to first-pass metabolism).
Oral: 90–100% for sustained-release formulation; food decreases rate but not extent (AUC unchanged).
No dose adjustment required for renal impairment.
No dose adjustment required for renal impairment.
No specific dose adjustment recommended; use caution in severe hepatic impairment.
Use with caution in severe hepatic impairment (Child-Pugh class C); consider dose reduction by 50%.
Children 5 years and older: 12 mcg inhalation twice daily. No dosing established for children under 5 years.
Children 6-12 years: 200-400 mcg inhaled twice daily. Children over 12 years: same as adult dose.
No specific dose adjustment; monitor for adverse effects due to potential comorbidities.
Start at lower end of dosing range (400 mcg twice daily) and titrate to response; monitor for systemic effects.
LABAs increase the risk of asthma-related death; Foradil should only be used in patients with asthma not adequately controlled on asthma controller medications or whose disease severity warrants initiation of both an inhaled corticosteroid and a LABA.
No FDA black box warning exists for this drug.
Increased risk of asthma-related death,Deterioration of disease and acute episodes may occur and should be treated with a short-acting beta2-agonist,Cardiovascular effects (increased heart rate, blood pressure, ECG changes),Hypokalemia and hyperglycemia may occur,Paradoxical bronchospasm may occur and require immediate discontinuation,Do not use with other LABAs
Theophylline has a narrow therapeutic index; serum levels must be monitored to avoid toxicity. Toxicity can include seizures, cardiac arrhythmias, and death. Caution in patients with heart failure, hepatic impairment, or those over 55 years. Risk of toxicity increased by concurrent medications such as cimetidine, fluoroquinolones, and macrolides.
Hypersensitivity to formoterol or any ingredient in the formulation,Use as monotherapy in asthma without concomitant inhaled corticosteroid,Treatment of acute asthma symptoms or exacerbations
Hypersensitivity to theophylline or any component of the formulation; active seizure disorder; untreated cardiac arrhythmias; severe hypertension; hyperthyroidism; peptic ulcer disease; caution with concurrent use of ephedrine or other sympathomimetics.
No specific food interactions. Grapefruit/grapefruit juice may increase systemic exposure via CYP3A4 inhibition; avoid concurrent use.
High-fat meals may delay absorption. Avoid charcoal-grilled foods and large amounts of caffeine. Grapefruit juice may increase theophylline levels; limit intake.
FDA Pregnancy Category C. In animal studies, formoterol fumarate (active ingredient of FORADIL) showed adverse effects on fetal development at high doses, including increased fetal loss, decreased fetal weight, and skeletal variations. There are no adequate and well-controlled studies in pregnant women. During first trimester, risk cannot be ruled out. Second and third trimesters: potential risk of maternal beta-agonist effects causing uterine relaxation and delayed labor. Use only if potential benefit justifies potential risk to fetus.
Pregnancy Category C. In first trimester: insufficient human data; animal studies show adverse effects at high doses. Second and third trimesters: may cause fetal tachycardia, hypoglycemia, and reduced uterine contractility; avoid use near term due to potential for neonatal bradycardia and hypoglycemia.
Formoterol is excreted in human milk in small amounts. M/P ratio not established. Caution should be exercised when administered to nursing women. Consider the developmental and health benefits of breastfeeding along with the mother's clinical need for FORADIL and any potential adverse effects on the breastfed infant from the drug or underlying maternal condition.
Salbutamol is excreted into breast milk in minimal amounts; estimated infant dose <2% of maternal weight-adjusted dose. No known adverse effects in nursing infants. M/P ratio not established. Use with caution.
No specific dose adjustments are recommended for FORADIL during pregnancy based on pharmacokinetic changes. However, use the lowest effective dose to control asthma symptoms. Monitor for potential increased need for rescue medication due to pregnancy-related changes in asthma severity. No data indicate significant pharmacokinetic changes requiring dosing modification.
No dose adjustment required for inhaled salbutamol. Increased clearance in late pregnancy may necessitate higher doses for systemic effects; monitor clinical response and adjust accordingly.
FORADIL (formoterol fumarate) is a long-acting beta2-agonist (LABA) indicated for maintenance treatment of asthma and COPD, but must not be used as monotherapy for asthma without concomitant inhaled corticosteroid. Onset of bronchodilation occurs within 5-10 minutes, peaking at 1-3 hours, with duration up to 12 hours. Not for acute bronchospasm. Risk of paradoxical bronchospasm; discontinue if occurs. Monitor for increased heart rate, blood pressure, and QTc prolongation. Caution in patients with cardiovascular disorders, seizure disorders, thyrotoxicosis, or diabetes.
AEROLATE SR contains theophylline; narrow therapeutic index (10-20 mcg/m L). Monitor serum levels, especially with CYP1A2 inhibitors (e.g., ciprofloxacin, fluvoxamine) or inducers (e.g., carbamazepine, phenytoin). SR formulation avoids peak-trough fluctuations; do not crush or chew. Caution in heart failure, hepatic impairment, and elderly.
Use FORADIL exactly as prescribed; do not use to relieve sudden breathing problems.,Always have a fast-acting rescue inhaler (e.g., albuterol) for acute symptoms.,Do not use more than 2 inhalations every 12 hours; maximum daily dose is 48 mcg.,Rinse mouth with water after each use to reduce risk of thrush (if using with ICS).,Seek medical help immediately if breathing worsens, chest tightness, or hives develop.,Inform your doctor if you have heart disease, high blood pressure, seizures, thyroid problems, or diabetes.,Store capsules in blister pack, use only with provided Aerolizer inhaler; do not swallow capsules.
Take exactly as prescribed; do not crush or chew the sustained-release tablet.,Do not stop suddenly; sudden withdrawal may worsen breathing.,Avoid excessive caffeine (coffee, tea, chocolate) as it may increase side effects.,Report nausea, vomiting, insomnia, palpitations, or seizures immediately.,Keep regular appointments for blood level monitoring.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about FORADIL vs AEROLATE SR, answered by our medical review team.
FORADIL is a Bronchodilator that works by Formoterol is a long-acting beta2-adrenergic receptor agonist (LABA) that relaxes bronchial smooth muscle by increasing intracellular cyclic AMP.. AEROLATE SR is a Bronchodilator that works by AEROLATE SR is a sustained-release formulation of theophylline, a methylxanthine bronchodilator. It acts by inhibiting phosphodiesterase (PDE) isoenzymes, leading to increased intracellular cyclic AMP (c AMP) levels. This results in relaxation of bronchial smooth muscle and suppression of the response of airways to stimuli. Theophylline also has anti-inflammatory effects, including inhibition of late-phase allergen-induced responses and reduction of eosinophil infiltration.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between FORADIL and AEROLATE SR depend on the specific clinical indication. These are both Bronchodilator agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of FORADIL is: Inhalation: 12 mcg twice daily (every 12 hours) via Foradil Aerolizer.. The standard adult dose of AEROLATE SR is: 400-800 mcg inhaled twice daily. For acute bronchospasm, 200-400 mcg as needed.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between FORADIL and AEROLATE SR in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. FORADIL is classified as Category C. FDA Pregnancy Category C. In animal studies, formoterol fumarate (active ingredient of FORADIL) showed adverse effects on fetal development at high doses, including increased fetal. AEROLATE SR is classified as Category C. Pregnancy Category C. In first trimester: insufficient human data; animal studies show adverse effects at high doses. Second and third trimesters: may cause fetal tachycardia, hypo. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.