Carbidopa/Levodopa: Carbidopa/Levodopa does not influence the pharmacokinetics of pramipexole in healthy
volunteers (N= 10). Mirapex did not alter the extent of absorption (AUC) or the elimination of carbidopa/
levodopa, although it caused an increase in levodopa Cmax by about 40% and a decrease in Tmax
from 2.5 to 0. 5 hours.
Selegiline: In healthy volunteers (N= 11), selegiline did not influence the pharmacokinetics of
Amantadine: Population pharmacokinetic analysis suggests that amantadine is unlikely to alter the oral
clearance of pramipexole (N= 54).
Cimetidine: Cimetidine, a known inhibitor of renal tubular secretion of organic bases via the cationic
transport system, caused a 50% increase in pramipexole AUC and a 40% increase in half-life (N= 12).
Probenecid: Probenecid, a known inhibitor of renal tubular secretion of organic acids via the aruonic
transporter, did not noticeably influence pramipexole pharmacokinetics (N= 12).
Other drugs eliminated via renal secretion: Population pharmacokinetic analysis suggests that
coadministration of drugs that are secreted by the cationic transport system (e.g., cimetidine, ranitidine,
diltiazem, triamterene, verapamil, quinidine, and quinine) decreases the oral clearance of pramipexole by about 20%,
while those secreted by the anionic transport system (e.g., cephalosporins, penicillins, indomethacin,
hydrochlorothiazide, and chlorpropamide) are likely to have little effect on the oral clearance of pramipexole.
CYP interactions: Inhibitors of cytochrome P450 enzymes would not be expected to affect
pramipexole elimination because pramipexole is not appreciably metabolized by these enzymes in vivo or in
vitro. Mirapex does not inhibit CYP enzymes CYPIA2, CYP2C9, CYP2CI9, CYP2EI, and CYP3A4. Inhibition of CYP2D6
was observed with an apparent Ki of 30 uM, indicating that pramipexole will not inhibit CYP enzymes at plasma
concentrations observed following the highest recommended clinical dose (1.5 mg tid).
Dopamine antagonists: Since pramipexole is a dopamine agonist, it is possible that dopamine antagonists,
such as the neuroleptics (phenothiazines, butyrophenones, thioxanthenes) or metoclopramide, may diminish the
effectiveness of MIRAPEX.
Drug/ Laboratory Test Interactions
There are no known interactions between MIRAPEX and laboratory tests.