Phenylbutazone Penicillamine

Atenolol, hydralazine, procainamide, quinidine, carbamazepine, chlorpromazine, ethosuximide, isoniazid, methyldopa, minocycline, penicillamine, phenylbutazone, phenytoin, thiazides, and valproic acid... 

Penicillamine Gold therapy, antimalarial or cytotoxic drugs, oxyphenbutazone or phenylbutazone A Do not use these drugs in patients who are concurrently receiving penicillamine. These drugs are associated with similar serious hematologic and renal reactions. 

Colitis, concurrent use of antimalarials, immunosuppressive agents, penicillamine, or phenylbutazone, congestive heart failure (CHF), exfoliative dermatitis, history of blood dyscrasias, severe liver or renal impairment, systemic lupus erythematosus... 

Penicillamine is contraindicated in patients with a history of penicillamine-related aplastic anemia or agranulo-cystosis in patients with significant renal or hepatic insufficiency in pregnant women and in patients receiving gold salts, immunosuppressants, antimalarials, or phenylbutazone because of the increased risk of serious hematologic effects. 

The list of compounds presented in Table 6.4 includes copper complexes of well-known antiarthritic drugs, including salicylic acid, aspirin, diflunisal, niflumic acid, D-penicillamine, hydrocortisone, dexamethasone, dimethyl-sul-phoxide, clopirac, ketoprofen, ibuprofen, (+ )-naproxen, indomethacin, me-fenamic acid, thiomalic acid, phenylbutazone, lonazolac, isoxicam and azo-propazone. While there has been much discussion concerning the qualitative and quantitative activities of these complexes [136, 152-156, 164, 187], it is... 

A. Penicillamine may potentiate the hematopoietic-depressant effects of drugs such as gold salts, immunosuppressants, antimalarial agents, and phenylbutazone. 

UK manufacturer lists carbamazepine (see also Clozapine + Anti epileptics , p.744), chloramphenicol, cytotoxics, penicillamine, pyrazolone analgesics (e.g. phenylbutazone), sulphonamides (e.g. co-trimoxazole) and, because they cannot be stopped if an adverse reaction occurs, they advise against the use of depot antipsychotics. There are several cases that confirm the clinical significance of these predicted interactions. 

Indometacin has been found to increase the AUC of penicillamine by 26% and the peak plasma levels by about 22%. The UK manufacturer notes that use of NSAIDs may increase the risk of renal damage with penicillamine. The US manufacturer specifically recommends avoiding oxy-phenbutazone or phenylbutazone because these drugs are also associated with serious haematological and renal effects. Urinalysis for detection of haematuria or proteinuria should be regularly carried out in patients taking penicillamine. Be alert for evidence of toxicity if NSAIDs and penicillamine are used together. 

Indomethacin and chloroquine have been implicated in causing mild sensorimotor neuropathy as well as vascular myopathy. Peripheral neuropathy has been reported in patients treated with penicillamine, but less often than the myasthenic syndrome that develop in some patients treated with this drug. Paresthesiae and muscle weakness have been reported in some patients treated with phenylbutazone (Argov and Mastaglia 1979). In all these sydromes, little evidence exists that they are caused by allergic mechanisms. 

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