Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
A/T/S vs ALEVE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
A/T/S (erythromycin) is a macrolide antibiotic that acts by binding to the 50S ribosomal subunit of susceptible bacteria, inhibiting protein synthesis and bacterial growth.
Naproxen, a nonsteroidal anti-inflammatory drug (NSAID), inhibits cyclooxygenase (COX-1 and COX-2) enzymes, thereby reducing prostaglandin synthesis. This leads to decreased inflammation, pain, and fever.
Treatment of acne vulgaris (FDA-approved indication),Treatment of bacterial infections caused by susceptible organisms (off-label use for acne is the primary use)
Rheumatoid arthritis,Osteoarthritis,Ankylosing spondylitis,Juvenile arthritis,Tendonitis,Bursitis,Acute gout,Primary dysmenorrhea,Mild to moderate pain,Fever
Dosing is individualized based on antithrombin activity level. For acute thrombotic events: initial bolus of 30-50 IU/kg followed by maintenance dosing to achieve target activity levels (80-120% of normal). Prophylaxis: 40-60 IU/kg every 24 hours.
220 mg orally every 8 to 12 hours as needed; maximum 660 mg per day.
Terminal elimination half-life: 1–2 hours (prolonged in hepatic impairment).
Terminal elimination half-life is 12-17 hours; allows twice-daily dosing for steady-state concentrations.
Antithrombin is a glycoprotein; its metabolism involves cellular uptake and catabolism, but specific CYP450 enzymes are not involved. Degradation occurs via proteolysis and reticuloendothelial system clearance.
Naproxen is extensively metabolized in the liver primarily via CYP2C9 to 6-O-desmethyl naproxen, and less than 5% is excreted unchanged in urine.
Renal: 10-20% (active drug and metabolites); Fecal: minimal; Biliary: not significant.
Renal (95% as unchanged drug and metabolites); biliary/fecal (5%)
70-90% bound to serum albumin.
>99% bound to albumin; saturable at high concentrations.
0.5–0.8 L/kg (low Vd, minimal tissue penetration).
0.16 L/kg; indicates distribution primarily in extracellular fluid.
Topical: 1–5% (minimal systemic absorption).
Oral: ~95%; immediate-release formulation.
No specific adjustment required; drug is not renally eliminated.
GFR 30-59 m L/min: reduce dose and avoid long-term use; GFR <30 m L/min: contraindicated.
No specific adjustment; antithrombin is produced in the liver, but exogenous replacement does not require dose adjustment in hepatic impairment.
Child-Pugh class A: no adjustment; Child-Pugh class B or C: avoid use.
Dosing based on weight and antithrombin levels; typical initial dose 30-50 IU/kg, followed by maintenance to achieve target levels. Clinical trial data limited in neonates.
2-12 years: 2.5-5 mg/kg/dose orally every 8-12 hours; maximum 10 mg/kg/day. 12 years and older: same as adult.
No specific adjustment; use standard dosing with monitoring of antithrombin activity and bleeding risk.
Initiate at lowest effective dose (220 mg every 12 hours); maximum 440 mg per day; monitor renal function and GI bleeding risk.
None.
Nonsteroidal anti-inflammatory drugs (NSAIDs) cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal. This risk may increase with duration of use. Patients with cardiovascular disease or risk factors may be at greater risk. Naproxen is contraindicated for treatment of peri-operative pain in the setting of coronary artery bypass graft (CABG) surgery. NSAIDs cause an increased risk of serious gastrointestinal adverse events including bleeding, ulceration, and perforation of the stomach or intestines, which can be fatal. These events can occur at any time during use and without warning symptoms. Elderly patients and patients with a prior history of peptic ulcer disease or GI bleeding are at greater risk.
Hypersensitivity reactions including anaphylaxis have occurred.,Prolonged use may result in overgrowth of nonsusceptible organisms including fungi.,Use with caution in patients with hepatic impairment.,Potential for QT prolongation and ventricular arrhythmias, especially with intravenous administration or concomitant drugs that prolong QT interval.
Cardiovascular thrombotic events,Gastrointestinal bleeding, ulceration, and perforation,Hypertension,Heart failure and edema,Renal toxicity,Anaphylactoid reactions,Serious skin reactions (e.g., Stevens-Johnson syndrome),Hematologic toxicity (inhibition of platelet aggregation),Exacerbation of asthma,Hepatic effects,Pregnancy: avoid during third trimester
Hypersensitivity to erythromycin or any macrolide antibiotic.,Use with caution in patients with pre-existing QT prolongation or electrolyte abnormalities (relative contraindication).
History of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs,Peri-operative pain in the setting of CABG surgery,Advanced renal disease,History of gastrointestinal bleeding or perforation related to previous NSAID therapy,Active gastrointestinal bleed
No specific food interactions. Avoid excessive alcohol consumption as it may increase skin dryness.
Avoid concurrent use of alcohol as it increases GI bleeding risk. No specific food restrictions; taking with food or milk may reduce dyspepsia. High potassium foods (e.g., bananas, spinach) may increase hyperkalemia risk in patients with renal impairment.
FDA Pregnancy Category B. No evidence of teratogenicity in animal studies; no adequate human studies in first trimester. Topical erythromycin has minimal systemic absorption; risk to fetus is low across all trimesters.
First trimester: Risk of spontaneous abortion and cardiac defects (odds ratio 1.86 for NSAIDs). Second trimester: Possible fetal renal dysfunction and oligohydramnios; ductus arteriosus premature closure risk begins. Third trimester: High risk of premature closure of ductus arteriosus, oligohydramnios, necrotizing enterocolitis, intracranial hemorrhage, and renal impairment; avoid after 30 weeks.
Compatible with breastfeeding. Erythromycin is excreted into breast milk in small amounts (M/P ratio approximately 0.5). Topical use results in negligible systemic exposure; unlikely to cause adverse effects in nursing infants.
Excreted in breast milk in low concentrations (M/P ratio ~0.12); relative infant dose <1% of maternal weight-adjusted dose. Compatible with breastfeeding; monitor infant for potential adverse effects (gastrointestinal upset, rash) at higher doses.
No dose adjustment required. Systemic absorption from topical application is minimal and not significantly altered by pregnancy-related pharmacokinetic changes.
No specific pharmacokinetic-based dose adjustments; however, use lowest effective dose for shortest duration, especially after 20 weeks. Avoid use after 30 weeks gestation due to fetal risks. Increased volume of distribution may reduce serum concentrations but no dose adjustment recommended.
A/T/S (erythromycin 2% topical solution) is indicated for acne vulgaris. Avoid contact with eyes, mouth, and mucous membranes. May cause skin dryness or irritation; use moisturizer. Effectiveness may decrease with prolonged use due to bacterial resistance. Not recommended for use with other topical erythromycin products or clindamycin to avoid antagonism.
ALEVE (naproxen sodium) is a nonsteroidal anti-inflammatory drug (NSAID) with a longer half-life (12-17 hours) allowing twice-daily dosing. It carries a boxed warning for cardiovascular and gastrointestinal risk. Use lowest effective dose for shortest duration. Contraindicated in patients with aspirin allergy, perioperative pain in CABG surgery, and significant renal impairment. Monitor renal function in elderly, volume-depleted patients, and those on ACE inhibitors or diuretics.
Apply a thin layer to affected areas twice daily after washing.,Avoid contact with eyes, lips, and mouth; if contact occurs, rinse thoroughly with water.,May cause stinging, burning, or peeling; if irritation persists, consult your doctor.,Use sunscreen daily as this medication may increase sensitivity to sunlight.,Do not use more than prescribed; overuse may increase side effects without improving results.,Inform your doctor if you are pregnant, planning to become pregnant, or breastfeeding.,Keep away from open flames or heat sources; product is flammable.
Take with food or milk to reduce GI upset.,Do not exceed 2 tablets (440 mg) in 24 hours unless directed by a doctor.,Avoid alcohol consumption to lower risk of GI bleeding.,Stop use and seek medical help if you experience chest pain, weakness, slurred speech, or signs of stomach bleeding (black/tarry stools, vomit that looks like coffee grounds).,Do not use with other NSAIDs (e.g., ibuprofen, aspirin) unless prescribed.
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 A/T/S vs ALEVE, answered by our medical review team.
A/T/S is a Macrolide antibiotic that works by A/T/S (erythromycin) is a macrolide antibiotic that acts by binding to the 50S ribosomal subunit of susceptible bacteria, inhibiting protein synthesis and bacterial growth.. ALEVE is a Nonsteroidal Anti-inflammatory Drug (NSAID) that works by Naproxen, a nonsteroidal anti-inflammatory drug (NSAID), inhibits cyclooxygenase (COX-1 and COX-2) enzymes, thereby reducing prostaglandin synthesis. This leads to decreased inflammation, pain, and fever.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between A/T/S and ALEVE depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of A/T/S is: Dosing is individualized based on antithrombin activity level. For acute thrombotic events: initial bolus of 30-50 IU/kg followed by maintenance dosing to achieve target activity levels (80-120% of normal). Prophylaxis: 40-60 IU/kg every 24 hours.. The standard adult dose of ALEVE is: 220 mg orally every 8 to 12 hours as needed; maximum 660 mg per day.. 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 A/T/S and ALEVE 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. A/T/S is classified as Category C. FDA Pregnancy Category B. No evidence of teratogenicity in animal studies; no adequate human studies in first trimester. Topical erythromycin has minimal systemic absorption; risk . ALEVE is classified as Category C. First trimester: Risk of spontaneous abortion and cardiac defects (odds ratio 1.86 for NSAIDs). Second trimester: Possible fetal renal dysfunction and oligohydramnios; ductus arter. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.