Clinically important drug interactions with disease-modifying antirheumatic drugs.
ABSTRACT Rheumatic diseases are mostly chronic in nature and often require long term drug treatment. An increasing number of disease-modifying antirheumatic drugs (DMARDs) are used earlier in the course of disease and increasingly in combination with each other. Often there is comorbidity with ensuing pharmacotherapy, especially in the elderly, and therefore the risk of unwanted drug interactions increases. Awareness of these interactions is important in order to either avoid or manage them. Antimalarials, gold, penicillamine (D-penicillamine), sulfasalazine and azathioprine have few clinically important drug interactions. The renal excretion of the antifolate methotrexate is affected by drugs that influence kidney function. This is of particular importance in patients with compromised renal function, e.g. the elderly. Other drugs with influence on folate metabolism, such as trimethoprim, should not be given concomitantly. Cyclosporin is an agent recently introduced in rheumatological practice, and shows a myriad of clinically significant drug interactions mainly based on interference with its metabolic degradation by cytochrome P450 3A, leading to increased or decreased blood concentrations and toxicity or lack of effect. Although most of these interactions with cyclosporin are described in organ transplant patients, they may apply to rheumatological practice as well.
Article: Elderly onset rheumatoid arthritis: differential diagnosis and choice of first-line and subsequent therapy.[show abstract] [hide abstract]
ABSTRACT: Elderly onset rheumatoid arthritis (EORA) has been considered a benign form of rheumatoid arthritis (RA). However, it most probably encompasses different subsets of patients with distinct outcomes. According to data reported in the most recent studies directly comparing older and younger RA patients, it seems that, overall, the prognosis of EORA patients is not very different from that of other patients with this disease. However, some cases with negative rheumatoid factor and polymyalgia-like symptoms appear to be a distinct subset with a different genetic basis and a more benign course. The differential diagnosis of EORA from other rheumatological disorders that are prevalent in this stratum of the population, such as polymyalgia rheumatica, crystal-induced arthritis or osteoarthritis, may be complicated because these disorders can present with signs and symptoms similar to those of RA in some circumstances. A prompt diagnosis of true RA is important because early treatment should be implemented. It is recommended that therapy of EORA be tailored according to disease activity, with the aim of achieving clinical remission or the lowest possible level of disease activity in order to minimize potential functional sequelae. Co-morbidities and drug toxicity profiles are major considerations when choosing the most suitable therapy for EORA patients. Prudent use and careful follow-up of all treatments are also required because of the increased risk of adverse events in elderly patients. However, no special contraindications to the use of disease-modifying antirheumatic drugs in this age group apply, and use of biological therapies currently used in younger RA patients has also been described in these patients. Therefore, a therapeutic strategy for first-line and subsequent treatment that is in accordance with the disease activity of patients with EORA is suggested.Drugs & Aging 02/2009; 26(9):739-50. · 2.67 Impact Factor