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Tiopronin Side Effects

For the Consumer

Applies to tiopronin: oral tablet

Along with its needed effects, tiopronin 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 tiopronin:

More common
  • Yellow skin or eyes
Less common

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

More common
  • Pain, swelling, or tenderness of the skin
  • skin rash, hives or itching
  • ulcers or sores in mouth
Less common
  • Bloody or cloudy urine
  • chills
  • difficulty in breathing
  • high blood pressure
  • hoarseness
  • joint pain
  • swelling of feet or lower legs
  • tenderness of glands
  • unusual bleeding
  • Chest pain
  • cough
  • difficulty in chewing, talking, or swallowing
  • double vision
  • general feeling of discomfort, illness, or weakness
  • muscle weakness
  • spitting up blood
  • swelling of lymph glands

Some side effects of tiopronin 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 Less common
  • Changes in taste or smell

For Healthcare Professionals

Applies to tiopronin: oral tablet


Hepatic side effects have included jaundice and abnormal liver function tests.[Ref]


Hypersensitivity side effects have included fever, rash (erythematous, maculopapular, or morbilliform), and pruritus. Laryngeal edema, dyspnea, respiratory distress, chills, arthralgia, weakness and adenopathy have also been reported.[Ref]

Patients experiencing immediate hypersensitivity reactions can be treated with antihistamines and tiopronin treatment restarted at a lower dose. Those experiencing a rash later in treatment (at least 6 months into therapy) usually cannot be restarted on tiopronin.[Ref]


Immunologic side effects have included a simulated lupus erythematous occasionally associated with a positive antinuclear antibody test.[Ref]


Gastrointestinal side effects have included hypogeusia. Nausea, emesis, diarrhea or soft stools, anorexia, abdominal pain, and bloating or flatulence have also been reported.[Ref]


Metabolic side effects have rarely included vitamin B6 deficiency.[Ref]


Dermatologic side effects have included wrinkling and friability of the skin. Ecchymosis, urticaria, warts, pemphigus, and elastosis perforans serpiginosa have also been reported.[Ref]


Hematological side effects have included increased bleeding, anemia, leukopenia, thrombocytopenia, and eosinophilia.[Ref]


Renal side effects have included proteinuria, nephrotic syndrome, and hematuria.[Ref]


Respiratory side effects have included pharyngitis, bronchiolitis, hemoptysis, and pulmonary infiltrates.[Ref]

Nervous system

Nervous system side effects have included myasthenic syndrome.[Ref]


1. "Product Information. Thiola (tiopronin)." Mission Pharmaceutical Company, San Antonio, TX.

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

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.