Brands, Medical Use, Clinical Data
Drug Category
- Free Radical Scavengers
- Antiparkinson Agents
- Antidyskinetics
- Antioxidants
Dosage Forms
Brands / Synonyms
Furfuryl Acetate; Mirapex; Pramipexol; Pramipexol [Spanish]; Pramipexole 2HCl Monohydrate; Pramipexole hydrochloride; Pramipexole [Usan:Inn]; Pramipexolum [Latin]; SUD919CL2Y
Indications
For the treatment of signs and symptoms of idiopathic Parkinson's disease
Pharmacology
Pramipexole is a nonergot dopamine agonist with high relative in vitro specificity and full intrinsic activity at the D2 subfamily of dopamine receptors, binding with higher affinity to D3 than to D2 or D4 receptor subtypes. The relevance of D3 receptor binding in Parkinson's disease is unknown. The precise mechanism of action of Pramipexole as a treatment for Parkinson's disease is unknown, although it is believed to be related to its ability to stimulate dopamine receptors in the striatum. This conclusion is supported by electrophysiologic studies in animals that have demonstrated that Pramipexole influences striatal neuronal firing rates via activation of dopamine receptors in the striatum and the substantia nigra, the site of neurons that send projections to the striatum.
Mechanism of Action
The precise mechanism of action of Pramipexole as a treatment for Parkinson's disease is unknown, although it is believed to be related to its ability to stimulate dopamine receptors in the striatum.
Absorption
Not Available
Toxicity
Not Available
Biotrnasformation / Drug Metabolism
Not Available
Contraindications
MIRAPEX Tablets are contraindicated in patients who have demonstrated hypersensitivity to the drug or its
ingredients.
Drug Interactions
Carbidopa/Levodopa: Carbidopa/Levodopa does not influence the pharmacokinetics of pramipexole in healthy
volunteers (N= 10). Pramipexole 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
pramipexole.
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. Pramipexole 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.
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