ISONIAZID Side Effects by Likelihood and Severity

COMMON side effects

If experienced, these tend to have a Severe expression i

  • a painful condition that affects the nerves in the legs and arms called peripheral neuropathy
  • inflammation of the liver called hepatitis

If experienced, these tend to have a Less Severe expression i

  • low levels of vitamin B6 in the blood
  • nausea
  • vomiting
  • diarrhea

INFREQUENT side effects

If experienced, these tend to have a Severe expression i

  • abnormal liver function tests

If experienced, these tend to have a Less Severe expression i

  • indigestion
  • irritation of the stomach or intestines

RARE side effects

If experienced, these tend to have a Severe expression i

  • excess body acid
  • a type of blood disorder where the red blood cells burst called hemolytic anemia
  • low blood counts due to bone marrow failure
  • decreased blood platelets
  • very low levels of granulocytes, a type of white blood cell
  • toxic psychosis
  • a type of brain function problem called encephalopathy
  • a toxic effect on the central nervous system, which consists of the brain and spinal cord
  • optic atrophy, a form of nerve damage in the eye
  • sudden blindness and pain upon moving the eye
  • inflammation of the blood vessels
  • low blood pressure
  • bronchospasm
  • inflammation of the skin due to an allergy
  • a skin disorder with blistering and peeling skin called toxic epidermal necrolysis
  • a skin disorder with blistering and peeling skin called Stevens-Johnson syndrome
  • a condition with symptoms that resemble lupus
  • seizures
  • a fever as a result of taking the medication
  • a skin rash
  • high amount of bilirubin in the blood
  • a type of allergic reaction called angioedema
  • a hypersensitivity reaction to a drug
  • pancreatitis
  • a type of significant allergic skin reaction called DRESS syndrome

If experienced, these tend to have a Less Severe expression i

  • pink eye
  • enlarged breasts
  • fever
  • flu-like symptoms
  • swollen lymph nodes

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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, except as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.