Abstract
The accumulation of chloroquine and hydroxychloroquine in unfractionated mononuclear cells and in purified monocytes, lymphocytes, and neutrophil polymorphonuclear leucocytes (PMN) was measured in vitro. Accumulation of both drugs in leucocytes was time and dose dependent. Cellular levels comparable to those found during antirheumatic therapy were achieved by preincubation for 60 minutes with up to 0.1 mM chloroquine or hydroxychloroquine.