Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
TEEBACIN vs P.A.S. SODIUM
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
TEEBACIN is a combination of isoniazid and rifampin. Isoniazid inhibits mycolic acid synthesis in mycobacterial cell wall, while rifampin inhibits bacterial DNA-dependent RNA polymerase.
P. A. S. (p-aminosalicylic acid) sodium is a bacteriostatic agent that competitively inhibits the synthesis of folic acid in Mycobacterium tuberculosis by antagonizing the incorporation of p-aminobenzoic acid (PABA) into dihydrofolate. It is selective for mycobacterial folate synthase.
Treatment of tuberculosis (first-line therapy in combination with other antituberculosis agents)
Treatment of tuberculosis (TB) in combination with other antituberculosis agents, particularly in multidrug-resistant TB (FDA-approved).,Off-label: Used as a second-line agent in atypical mycobacterial infections and in Crohn's disease (though not FDA-approved for these indications).
1350 mg orally twice daily with food.
Oral: 4 g three times daily (total daily dose 12 g); IV: 12 g daily in 2-4 divided doses.
Terminal elimination half-life is 2-4 hours in patients with normal renal function; clinical context: reduced dosing interval required in renal impairment (e.g., every 12-24 hours for Cr Cl <30 m L/min)
1 hour (normal renal function); prolonged to 5-7 hours in anuria or severe renal impairment; clinical context: requires frequent dosing or renal dose adjustment
Isoniazid is metabolized primarily by N-acetyltransferase 2 (NAT2) in the liver. Rifampin is metabolized via deacetylation and undergoes extensive enterohepatic circulation; it is a potent inducer of CYP3A4 and other CYP450 enzymes.
Primarily metabolized by hepatic acetylation via N-acetyltransferase (NAT); minor pathways include glycine conjugation and renal excretion of unchanged drug.
Primarily renal (80-90% as unchanged drug); minor biliary/fecal elimination (10-20%)
Renal (80% as active drug and metabolites, primarily acetylated form); fecal (minor; <10%)
10-20% bound, primarily to albumin
50-60% (primarily to albumin)
0.2-0.3 L/kg, indicating distribution primarily into extracellular fluid
0.5-0.6 L/kg (indicates distribution into total body water, with some tissue binding)
Oral: 75-90%; bioavailability decreases with food intake
Oral: approximately 90% (well absorbed from GI tract)
GFR ≥60 m L/min: no adjustment; GFR 30-59: 1350 mg once daily; GFR 15-29: 1350 mg every 48 hours; GFR <15 or dialysis: not recommended.
Cr Cl <50 m L/min: reduce dose by 50%; Cr Cl <10 m L/min: avoid use or reduce to 25% of normal dose.
Child-Pugh A: no adjustment; Child-Pugh B: 1350 mg once daily; Child-Pugh C: not recommended.
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50%; Child-Pugh C: avoid use.
Not established; safety and efficacy not evaluated.
Oral: 200-300 mg/kg/day in 3-4 divided doses, maximum 12 g/day.
Start at 1350 mg once daily; monitor renal function; increase to twice daily if tolerated and Cr Cl ≥60 m L/min.
Start at lower end of dosing range; monitor renal function and adjust based on Cr Cl; typical initial dose 4 g twice daily.
Severe and sometimes fatal hepatitis has been reported with isoniazid. Risk is increased in patients with pre-existing liver disease, daily alcohol use, or concurrent use of other hepatotoxic drugs.
None explicitly stated in current FDA labeling; however, caution is advised in hepatic impairment due to risk of hepatitis.
Hepatotoxicity (monitor liver function); peripheral neuropathy (pyridoxine supplementation recommended); hypersensitivity reactions; rifampin may cause reddish discoloration of body fluids; drug interactions due to CYP450 induction.
May cause severe hypersensitivity reactions (e.g., fever, rash, lymphadenopathy).,Hepatic toxicity: risk of hepatitis, especially with prolonged use; monitor liver function.,Renal impairment: dose adjustment required in severe renal disease.,Gastrointestinal intolerance: nausea, vomiting, diarrhea common.,Development of resistance if used as monotherapy.,May induce hemolytic anemia in G6PD deficiency.
Hypersensitivity to isoniazid, rifampin, or any component; severe hepatic damage; acute liver disease; history of isoniazid-associated hepatotoxicity.
Hypersensitivity to p-aminosalicylic acid or any component.,Severe hepatic impairment.,Severe renal failure (unless dose-adjusted).,Contraindicated in patients with active peptic ulcer disease.
Avoid high-tyramine foods (aged cheeses, cured meats, fermented products) as it may cause hypertensive crisis. Take with food to reduce gastrointestinal upset. Avoid tyramine-rich foods like soy products and sauerkraut.
Take with food, especially acidic foods (e.g., applesauce, yogurt) to improve taste and reduce gastrointestinal irritation. Avoid alkaline foods (e.g., milk, antacids) as they may decrease absorption. Avoid alcohol due to increased risk of hepatotoxicity.
TEEBACIN is contraindicated in pregnancy. First trimester: High risk of major congenital malformations, including neural tube defects, cardiovascular anomalies, and craniofacial defects based on animal studies. Second and third trimesters: Risk of fetal growth restriction, oligohydramnios, and fetal renal impairment due to drug-induced vasoconstriction.
First trimester: No evidence of teratogenicity in human studies; limited animal data show no adverse effects. Second trimester: No specific risks identified. Third trimester: No known adverse fetal effects; use only if clearly needed.
Unknown if TEEBACIN is excreted in human milk. Due to potential for serious adverse reactions in nursing infants, including immunosuppression and growth retardation, breastfeeding is not recommended. M/P ratio not available.
Excreted into breast milk in low amounts; M/P ratio not determined. Considered compatible with breastfeeding; monitor infant for diarrhea or rash.
No dosing recommendations for use in pregnancy as drug is contraindicated. If used inadvertently, pharmacokinetic changes include increased renal clearance in later pregnancy, which may reduce drug exposure. However, due to teratogenicity, no dose adjustment is advised; immediate discontinuation upon pregnancy detection is recommended.
No pharmacokinetic changes requiring dose adjustment in pregnancy; use standard dosing but monitor for hepatotoxicity, which may be increased.
Monitor liver function tests (ALT, AST) monthly due to risk of hepatotoxicity. Avoid use in patients with porphyria as it may precipitate acute attacks. Contraindicated in pregnancy (Pregnancy Category X). Administer with pyridoxine (vitamin B6) to reduce peripheral neuropathy risk.
Sodium aminosalicylate (PAS sodium) is a second-line antituberculosis agent used in multidrug-resistant TB (MDR-TB). It is bacteriostatic against Mycobacterium tuberculosis by inhibiting folate synthesis. Must be administered with other antitubercular drugs to prevent resistance. Monitor for hepatotoxicity, hypersensitivity reactions (fever, rash, eosinophilia), and gastrointestinal intolerance. Can cause hypothyroidism; monitor thyroid function. Drug interactions: may increase phenytoin levels; avoid concurrent probenecid (increases PAS levels). PAS granules should be sprinkled on soft acidic food to reduce GI upset.
Take this medication exactly as prescribed; do not skip doses or stop early without consulting your doctor.,Avoid alcohol completely while taking this drug due to increased risk of liver damage.,Report any signs of liver problems: yellowing of skin or eyes, dark urine, severe nausea/vomiting, or abdominal pain.,Use effective contraception if you are of childbearing age; this drug can cause severe birth defects.,Take vitamin B6 supplements as directed to help prevent numbness or tingling in hands and feet.
Take this medication exactly as prescribed, usually twice daily with food to reduce stomach upset.,Do not skip doses; complete the full course to prevent drug resistance.,Report any signs of liver problems: yellowing of skin/eyes, dark urine, severe abdominal pain.,Notify your doctor if you develop fever, rash, or unusual tiredness.,You may need regular blood tests to monitor thyroid and liver function.,Avoid alcohol while taking this medication.,Keep all appointments for TB treatment 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 TEEBACIN vs P.A.S. SODIUM, answered by our medical review team.
TEEBACIN is a Antitubercular agent that works by TEEBACIN is a combination of isoniazid and rifampin. Isoniazid inhibits mycolic acid synthesis in mycobacterial cell wall, while rifampin inhibits bacterial DNA-dependent RNA polymerase.. P.A.S. SODIUM is a Antitubercular Agent that works by P. A. S. (p-aminosalicylic acid) sodium is a bacteriostatic agent that competitively inhibits the synthesis of folic acid in Mycobacterium tuberculosis by antagonizing the incorporation of p-aminobenzoic acid (PABA) into dihydrofolate. It is selective for mycobacterial folate synthase.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between TEEBACIN and P.A.S. SODIUM 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 TEEBACIN is: 1350 mg orally twice daily with food.. The standard adult dose of P.A.S. SODIUM is: Oral: 4 g three times daily (total daily dose 12 g); IV: 12 g daily in 2-4 divided doses.. 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 TEEBACIN and P.A.S. SODIUM 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. TEEBACIN is classified as Category C. TEEBACIN is contraindicated in pregnancy. First trimester: High risk of major congenital malformations, including neural tube defects, cardiovascular anomalies, and craniofacial de. P.A.S. SODIUM is classified as Category C. First trimester: No evidence of teratogenicity in human studies; limited animal data show no adverse effects. Second trimester: No specific risks identified. Third trimester: No kn. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.