Rivastigmine pharmacokinetics

A small study suggests that HRT treatment can almost double the serum levels of tacrine. Limited evidence suggests that oestrogens do not affect rivastigmine pharmacokinetics. 

In contrast, analysis of population data from 70 subjects found that oestrogens did not affect rivastigmine pharmacokinetics. ... 

Lefevre, G., Pommier, F., Sedek, G., Allison, M., Huang, H.L., Kiese, B., Ho, Y.Y. and Appel-Dingemanse, S. (2008) Pharmacokinetics and bioavailahdity of the novel rivastigmine transdermal patch versus rivastigmine oral solution in healthy elderly subjects. Journal of Clinical Pharmacology, 48, 246—252. 

Roskos LK, Boudinot ED Effects of dose and sex on the pharmacokinetics of piroxicam in the rat. Biopharm Drug Dispos 11 215-225, 1990 Rosier M, Anand R, Cici-Sain A, et al Efficacy and safety of rivastigmine in patients with Alzheimer s disease international randomized controlled trial. BMJ 318 633-640, 1999... 

Because rivastigmine is not hepatically metabolized, pharmacokinetic cytochrome P450-related drug interactions are not expected. However, the previously discussed pharmacodynamic interactions associated with other cholinesterase inhibitors may occur with rivastigmine as well. 

Abstract Alzheimer s disease is an illness that affects not only the pahents themselves but also those around them. Traditionally, cholinesterase inhibitors have been the first-line medications used in treating Alzheimer s disease. There are currently fom approved cholinesterase inhibitors tacrine, donepezil, rivastigmine, and galantamine. Each of these medications has a unique pharmacokinetic profile and mechanism of action. Researchers in the past 5-10 years have accumulated much data on the use of cholinesterase inhibitors. The use of cholinesterase inhibitors may preserve activities of daily living, slow progression of memory loss, and improve behavioral and cognitive symptoms associated with Alzheimer s and other related dementias. There is also some evidence to suggest that the efficacy in some cases may last more than a few years. In addition, there is some evidence that the use of cholinesterase inhibitors may be associated with reduction of caretaker stress. The use of cholinesterase inhibitor, however, does not drastically improve... 

J. V. Gobburu, V. Tammara, L. Lesko, S. S. Jhee, J. J. Sramek, N. R. Cutler, and R. Yuan, Pharmacokinetic-pharmacodynamic modeling of rivastigmine, a choUnesterase inhibitor, in patients with Alzheimer s disease. / Clin Pharmacol 41 1082-1090 (2001). 

Diazepam does not appear to affect the pharmacokinetics of tacrine or rivastigmine. 

In a small study a single 2-mg dose of diazepam did not affeet the pharmacokinetics of tacrine 20 mg every 6 hours, when compared with subjects not taking diazepam. Similarly the manufacturers of rivastigmine say that no pharmacokinetic interaction has been seen with diazepam in healthy subjects. No special precautions would seem necessary if diazepam is given with tacrine or rivastigmine. 

Fluvoxamine markedly increases the levels of tacrine, and increases its cholinei ic adverse effects, whereas fluoxetine, paroxetine, and sertraline are not expected to interact. Paroxetine and fluoxetine may increase donepezil and galantamine levels. Sertraline does not appear to have a pharmacokinetic interaction with donepezil, and concurrent use seems generally well tolerated however, one report describes hepatotoxicity, possibly as a result of their concurrent use. Rivastigmine and fluoxetine appear not to interact. 

The manufacturers of rivastigmine report that in studies in healthy subjects no pharmacokinetic interactions were seen between rivastigmine and fluoxetine. No special precautions appear necessary. 

Donepezil, galantamine, rivastigmine and tacrine do not appear to alter the pharmacokinetics or effects of warfarin. 

Similarly, the manufacturers of galantamine say that no pharmacokinetic interactions have been seen with digoxin, but caution about the possibility of a pharmacodynamic interaction that may result in bradycardia. The manufacturers of rivastigmine say that the combination has no pharmacokinetic interaction, nor does it interfere with cardiac conduction. It would however seem prudent to monitor heart rate if any of these combinations are used. 

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