Penicillamine
Synonyms :
Cuprimine, D Penicillamine
Mechanism :
As a chelating agent, penicillamine removes copper and lead from the body.
Penicillamine also reduces excess cystine excretion in cystinuria. This is done, at least in part, by disulfide interchange between penicillamine and cystine, resulting in formation of penicillamine-cysteine disulfide, a substance that is much more soluble than cystine and is excreted readily.
Indication :
- Wilson’s disease
- Lead poisoning
- Juvenile idiopathic arthritis
- Cystinuria
Contraindications :
Contraindicated in pregnancy, lactation, in patients with a history of penicillamine-related aplastic anemia or agranulocytosis, in rheumatoid arthritis, patients with a history or other evidence of renal insufficiency and in patients with chronic lead poisoning when there is x-ray evidence of lead-containing substances in the gastrointestinal tract. Penicillamine should not be used in patients who are receiving gold therapy, antimalarial or cytotoxic drugs, oxyphenbutazone or phenylbutazone because these drugs are also associated with similar serious hematologic and renal adverse reactions.
Dosing :
Oral
Wilson’s disease/Cystinuria:
20-30 mg/kg/24 hours in 2 divided doses. Max: 1 gm/24 hours.
Lead intoxication:
20-40 mg/kg/24 hours in 3 divided doses. Max: 1.5 gm/24 hours.
Juvenile idiopathic arthritis:
5 mg/kg every 24 hours for 2 months.
10 mg/kg every 24 hours for 4 months.
Adverse Effect :
Urticaria and exfoliative dermatitis, anorexia, epigastric pain, nausea, vomiting, occasional diarrhea, drug eruptions (fever, arthralgia, or lymphadenopathy), lupus erythematosus-like syndrome, thyroiditis, migratory polyarthralgia, bone marrow depression, hemolytic anemia, red cell aplasia, eosinophilia, proteinuria and/or hematuria, tinnitus, optic neuritis, peripheral sensory and motor neuropathies, myasthenia gravis.
Interaction :
Sucralfate, Antacids and Iron Preparations: May substantially reduce the absorption
Renal Dose :
Dose in Renal Impairment GFR (mL/min)
| 20-50 | Avoid if possible or reduce dose. 125 mg for first 12 weeks. Increase by same amount every 12 weeks |
| 10-20 | Avoid – nephrotoxic |
| <10 | Avoid – nephrotoxic |
Dose in Patients undergoing Renal Replacement Therapies
| CAPD | Unknown dialysability. Avoid – nephrotoxic |
| HD | Dialysed. 125–250 mg 3 times a week after HD |
| HDF/High flux | Dialysed. 125–250 mg 3 times a week after HD |
| CAV/VVHD | Unknown dialysability. Avoid – nephrotoxic |
Hepatic Dose :
No dose adjustment recommended.