Aminosalicylic Acid

Name: Aminosalicylic Acid




End-stage renal disease


Monitor liver function; reports of drug-induced hepatitis with rapidly absorbed aminosalicylic acid preparations

Aminosalicylic Acid Dosage and Administration


Oral Administration

Administer orally.102 Has been administered IV, but a parenteral preparation is not commercially available in the US.104

The delayed-release granules (Paser) have an acid-resistant coating designed to protect against degradation in the stomach so that the drug is released gradually and high peak concentrations are avoided.102

To protect the acid-resistant coating, administer the granules in food or drink with a pH <5.102 The granules can be sprinkled on applesauce or yogurt.102 Alternatively, they can be suspended in a fruit drink (e.g., orange, apple, tomato, grapefruit, grape, or cranberry juices, “fruit punch”); the granules will sink in the juice and must be resuspended by swirling.102 The granules should be swallowed whole without chewing.102

Patients receiving antacids do not need to take the delayed-release granules in an acidic food or drink.102


Should not be used alone for treatment of active (clinical) TB; must be given in conjunction with other antituberculosis agents.102 104

Data not available to date to support use of aminosalicylic acid in intermittent (e.g., 1–3 times weekly) multiple-drug TB regimens.104

Pediatric Patients

Tuberculosis Treatment of Active (Clinical) Tuberculosis Oral

Children <15 years of age or weighing ≤40 kg: 200–300 mg/kg daily (up to 10 g daily) given in 2–4 divided doses recommended by ATS, CDC, IDSA, and AAP.104 107

Adolescents ≥15 years of age: 8–12 g daily given in 2 or 3 divided doses recommended by ATS, CDC, and IDSA.104


Tuberculosis Treatment of Active (Clinical) Tuberculosis Oral

Manufacturer recommends 4 g 3 times daily.102

8–12 g daily given in 2 or 3 doses recommended by ATS, CDC, and IDSA.104 There is some evidence that 4 g twice daily achieves target serum concentrations.104 109

Prescribing Limits

Pediatric Patients

Treatment of Active (Clinical) Tuberculosis Oral

Maximum 10 g daily recommended by ATS, CDC, IDSA, and AAP.104 107

Special Populations

Hepatic Impairment

Dosage adjustment not necessary, but increased clinical and laboratory monitoring recommended.104 Clearance is not altered in patients with hepatic impairment, but these patients may not tolerate the drug as well as those with normal hepatic function.102

Renal Impairment

Contraindicated in severe renal disease (end-stage renal disease).102

Some experts recommend 4 g twice daily for treatment of active TB in patients with Clcr <30 mL/minute or undergoing hemodialysis.104 112 Doses should be given after hemodialysis104 since the drug is removed by this procedure;104 112 supplemental doses not necessary.112




Delayed-release Granules

<15°C (i.e., in a refrigerator or freezer) prior to dispensing.102 After dispensing, store in a refrigerator or freezer; may be stored at room temperature for short periods of time.102 Avoid exposure to excessive heat, moisture, or light.102 a

Do not use if the airtight package containing the granules is swollen.102 Do not use if the granules have lost their tan color and are turning dark brown or purple.102

Actions and Spectrum

  • Bacteriostatic in action.102

  • Mechanism of action is similar to that of sulfonamides.a Aminosalicylic acid prevents synthesis of folic acid in susceptible organisms by competitively blocking conversion of aminobenzoic acid to dihydrofolic acid.a

  • Highly specific antibacterial agent; active only against M. tuberculosis.a Inactive against M. avium complex (MAC) and other mycobacteria.a

  • Natural and acquired resistance to aminosalicylic acid demonstrated in vitro and in vivo.111 a

  • No evidence of cross-resistance between aminosalicylic acid and other antituberculosis agents currently available in the US.a

Uses of Aminosalicylic Acid

  • It is used to treat TB (tuberculosis).

What are some other side effects of Aminosalicylic Acid?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Belly pain.
  • Upset stomach or throwing up.
  • Loose stools (diarrhea).
  • You may see parts of aminosalicylic acid in your stool. This is normal and not a cause for concern.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at

Brand Names U.S.

  • Paser

Dosing Pediatric

Tuberculosis (second-line agent):

Children ≤40 kg and Adolescents <15 years: Oral: 200 to 300 mg/kg/day (usually 100 mg/kg/dose 2 to 3 times daily). Note: Use in combination with other antituberculous agents (Nahid 2016).

Children >40 kg and Adolescents ≥15 years: Refer to adult dosing.


May be administered with food. Do not use granules if packet is swollen or if granules are discolored (ie, brown or purple). Granules may be sprinkled on applesauce or yogurt (do not chew) or suspended in tomato or orange juice.

For the Consumer

Applies to aminosalicylic acid: oral tablet

Along with its needed effects, aminosalicylic acid may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking aminosalicylic acid:

More common
  • Fever
  • joint pains
  • skin rash or itching
  • unusual tiredness or weakness
Less common
  • Abdominal pain (severe)
  • backache
  • headache
  • lower back pain
  • pain or burning while urinating
  • paleness of skin
  • sore throat
  • yellow eyes or skin

Check with your doctor as soon as possible if any of the following side effects occur while taking aminosalicylic acid:

Less common - with long-term, high-dose therapy
  • Changes in menstrual periods
  • decreased sexual ability in males
  • dry, puffy skin
  • swelling of front part of neck
  • weight gain (unusual)

Some side effects of aminosalicylic acid may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common
  • Diarrhea
  • loss of appetite
  • nausea and vomiting
  • stomach pain (mild)

For Healthcare Professionals

Applies to aminosalicylic acid: compounding powder, oral granule enteric coated


Gastrointestinal side effects have been reported the most frequently. These have included nausea, vomiting, and abdominal pain.[Ref]

The incidence of gastrointestinal side effects is reduced with lower doses (8 g daily) and with the granular formulation of the drug.[Ref]


Hypersensitivity side effects have been reported rarely. The first signs have included rash, often followed by fever, and much less frequently, anorexia, nausea or diarrhea. The drug has been restarted in small but gradually increasing doses under a closely followed desensitization protocol.[Ref]


Patients should be closely monitored during the first three months of therapy and treatment must be discontinued immediately at the first signs of rash, fever, jaundice, or other sign of intolerance.[Ref]

Hepatic side effects have included jaundice and hepatitis. In patients diagnosed with hepatitis, hepatomegaly was invariably present with lymphadenopathy (45%), leukocytosis (79%), and eosinophilia (55%). Prompt recognition of symptoms with discontinuation of therapy led to recovery. Failure to recognize symptoms of liver injury can result in a mortality of up to 21%.[Ref]


A reduction in thyroxine synthesis has been associated with the administration of the sodium salt of aminosalicylic acid. The development of goiter can be prevented by the administration of thyroxine but not iodide.[Ref]

Endocrine side effects have included hypothyroidism, especially with prolonged administration. It may be accompanied by goiter development.[Ref]


Hematologic side effects have included leukopenia, agranulocytosis, thrombocytopenia, Coombs' positive hemolytic anemia, and reduction in prothrombin.[Ref]

Some side effects of aminosalicylic acid may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Administrative Information

LactMed Record Number


Last Revision Date



Information presented in this database is not meant as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. The U.S. government does not warrant or assume any liability or responsibility for the accuracy or completeness of the information on this Site.

Pregnancy & Lactation

Pregnancy Category: C

Lactation: Distributed in human breast milk; caution advised

Pregnancy Categories

A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

NA: Information not available.