Statins & Clarithromycin (antibiotic) may be deadly comb

[cjbrooksjc]

Statin induced rhabdomyolysis may be triggered by co-administration of Clarithromycin and Statins.

The antibiotic Clarithromycin is a potent inhibitor of CYP3A4, the major enzyme responsible for simvastatin, lovastatin, and atorvastatin metabolism.

Effects of Clarithromycin on the Pharmacokinetics of Simvastatin. Compared with simvastatin alone, coadministration of clarythromycin and simvastatin significantly increased the peak concentration and the area under the curve for simvastatin by approximately 8-fold (p<0.0001). Levels of simvastatin acid were also significantly (about 14-fold) higher during clarythromycin treatment compared with simvastatin alone (p<0.0001).
If the figures on pharmacokinetics from that last article are to be believed then 500 mg of clarithromycin magnifies 80 mg of daily simvastatin to an equivalent daily dose of 640 to 1,120 mg.

That is no error !! 640 to 1,120 mg PER DAY !!

You would do well to check your Rx history (while under statin therapy) to see if you may have been exposed to this interaction.

Link: **http://www.pbfluids.com/2009/11/how-do-you-go-from-egd-to-acute-kidney.html

Best,

Brooks

[Ray Holder]

I wonder if clarithromycin is another of those drugs which inhibit carnitine transporters, referred to in a recent link. I have had erythromycin recently, which has reduced my strength and overnight energy availability, I also had vancomycin a year ago, and recent papers have shown that both of these inhibit the carnitine transporters considerably. As Clarithromycin is apparently a modified form of erythromycin, I think it more than probable that it affects these transporters in a similar way.

This is a quite recent subject for research, and although I saw a list of 46 common drugs which did the same thing, I have only been able to get abstracts of the papers in the last few days, and not the list. There seems to be littlle one can do to ease the problem, and I have been trying all sorts of things to compensate for the lack of overnight carnitine, which is diminishing my heart strength in the small hours.
Googling "carnitine transporters inhibition drugs", some papers will be revealed, mainly of a theoretical and in vitro or animal experimentation, but it obviously has important ramifications for those who may already be deficient in carnitine.

Ray

[Biologist]

Both clarithromycin and erythromycin are listed with a concomitant warning on the Product Label for Zocor; vancomycin, and of course, doxycycline are not (while I have demonstrated by my own injuries, and also via the hyperlink below, that doxycycline should be).

*http://www.umm.edu/altmed/drugs/simvastatin-114850.htm

(Word search "doxycycline" to find it.)

There is no reason to believe that vancomycin is not equally damaging to the statin patient (or former statin patient) as any of the others that are listed. Pharma has no credibility here. I have documented other anomalies whereby other drugs were misclassified on the Label as being mild where they should have been upgraded to significant regarding their interactions.

I will be avoiding all antibiotics as much as possible in the future.

Biologist

[eml256]

Statin : metabolism site

Atorvastatin : 3A4
Fluvastatin (lescol) : 2C9, 2C8, 3A4
Lovastatin (mevacor): 3A4
Pravastatin (pravachol) : 3A4 (minimal metabolism here)
Rosuvastatin (crestor) : 2C9 (again minimal
metabolism here)
Simvastatin (zocor) : 3A4, 2D6

Potent inhibitors of 3A4 are: sporanox, ketoconazole, ritonavir, cipro, clarithromycin (biaxin), erythromycin, cyclosporine, efavirenz, Kaletra, nefazodone, and grapefruit juice.
Potent inhibitors of 2C9 (and thus impact crestor and lescol metabolism) are: diflucan, luvox and ritonavir.

In addition, llipitor, lescol and zocor are moderate to potent inhibitors of 2C9.

[eml256]

biologist, thanks for the web link to the univ of maryland med school site. it is excellent. madelyn