Indications
Penicillamine is used to treat Wilson’s disease (a rare inherited condition in which copper builds up in the liver, brain and other organs), cystinuria (a condition causing cystine kidney stones), and severe active rheumatoid arthritis that has not responded to other treatments. It is also sometimes used for lead poisoning and certain types of chronic hepatitis, as directed by a specialist.
How It Works
Penicillamine is a chelating agent. In Wilson’s disease, it binds copper in the body to form a complex that is passed out in the urine, lowering harmful copper levels. In cystinuria, it combines with cystine to form a more soluble compound, which helps prevent and dissolve kidney stones. In rheumatoid arthritis, it acts as a slow-acting disease-modifying drug that calms parts of the immune response, although exactly how is not fully understood.
Dosage and Administration
Take exactly as prescribed by your specialist. The dose depends on the condition and is usually started low and increased gradually. Take it on an empty stomach, at least 1 hour before or 2 hours after food, and at least 2 hours apart from iron, zinc, antacids, milk and other supplements. Your doctor may also prescribe Pyridoxine (vitamin B6), because Penicillamine can lower its levels. Improvement in arthritis may take 2 to 3 months.
Interactions
- Iron, Zinc, antacids and food reduce absorption; take them separately.
- Gold compounds, antimalarials (such as Chloroquine), Phenylbutazone and immunosuppressants increase the risk of serious blood and kidney side effects; avoid combining unless a specialist advises.
- Digoxin levels may be lowered.
- Clozapine and other medicines that can lower white blood cells add to the risk of blood disorders.
Contraindications
- Allergy to Penicillamine.
- Previous aplastic anaemia, agranulocytosis or severe low platelets caused by Penicillamine.
- Lupus (systemic lupus erythematosus).
- Moderate to severe kidney impairment (in rheumatoid arthritis).
- Pregnancy and breastfeeding when used for rheumatoid arthritis or cystinuria.
Side Effects
Common side effects include loss of appetite, nausea, vomiting, loss or change of taste, mouth ulcers, skin rash and itching, and protein in the urine. More serious effects include low white cells, platelets or red cells, kidney inflammation, lupus-like illness, myasthenia gravis (muscle weakness with drooping eyelids or double vision), lung problems, liver problems, skin blistering conditions and wrinkly or fragile skin with long-term use. In Wilson’s disease, nerve symptoms can sometimes worsen when treatment starts.
Stop taking it and get urgent medical help if you have fever, sore throat or mouth ulcers with signs of infection, unusual bleeding or bruising, blood in the urine or swollen ankles, a blistering rash, muscle weakness, drooping eyelids, double vision or difficulty swallowing, shortness of breath or cough, or yellow skin or eyes.
Pregnancy and Lactation
Penicillamine may harm an unborn baby. In Wilson’s disease, treatment is usually continued during pregnancy at the lowest effective dose under specialist care, because stopping it can be dangerous for the mother. It should not be used during pregnancy for rheumatoid arthritis or cystinuria. It may pass into breast milk; breastfeeding is generally not recommended, so discuss with your specialist.
Precautions and Warnings
- Regular blood counts and urine tests are needed, usually every 1 to 2 weeks for the first months and then monthly.
- Report any sign of infection, bleeding or rash immediately.
- People allergic to Penicillin may rarely react to Penicillamine.
- Drink plenty of water if treated for cystinuria.
- Surgery: wound healing may be slower; tell the surgeon you take it.
Overdose
There is limited information on overdose. Symptoms may include nausea, vomiting and worsening of side effects. Seek medical help; treatment is supportive with monitoring of blood and kidney function.
Therapeutic Class
Chelating agent; disease-modifying antirheumatic drug (DMARD).
Storage
Store below 30°C in a dry place, away from light, and out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.