Rifampin-how long

[cobbiemommy]

DS, 13, has been put back on Rifampin along with Clarithromycin. He has been on it about a week and we are having some herx symptoms, painfuls heels/shins and bright rash all over his torso. He also is chatty, chatty, chatty. Driving me crazy with all his talking....

 

How long does it take for Rifampin/Biaxin to finish the job? He was on this before and did well, but we still had a strep issue to clear up. He is getting IVIg every eight weeks for immunodeficiency.

 

Dr. J has him on 150 mg twice a day. This dosage seems low as he is 5'6" and weighs over 180. (not good, I know) Previously, he was taking 300 mg twice a day. Any thoughts???

 

Cobbie

[red]

DS, 13, has been put back on Rifampin along with Clarithromycin. He has been on it about a week and we are having some herx symptoms, painfuls heels/shins and bright rash all over his torso. He also is chatty, chatty, chatty. Driving me crazy with all his talking....

 

How long does it take for Rifampin/Biaxin to finish the job? He was on this before and did well, but we still had a strep issue to clear up. He is getting IVIg every eight weeks for immunodeficiency.

 

Dr. J has him on 150 mg twice a day. This dosage seems low as he is 5'6" and weighs over 180. (not good, I know) Previously, he was taking 300 mg twice a day. Any thoughts???

 

Cobbie

You ask how long it takes. Everybody is different as to how long it takes to work. Are you sure the bright rash all over his torso is not an allergic reaction??

I barely can tolerate pediatric doses of rifampin.

I think your doctor is not aware of that using rifampin results in up to 90% reduction in clarithromycin in the blood stream. Rifampin is a very powerful drug that due to its metabolization prevents many other drugs effectiveness. See Clinical pharmacokinetics of clarithromycin http://www.ncbi.nlm.nih.gov/pubmed/10589373

Concentration of clarithromycin and 14-R-hydroxy-clarithromycin in plasma of patients with Mycobacterium avium complex infection, before and after the addition of rifampicin. http://www.ncbi.nlm.nih.gov/pubmed/15116577

Reduced serum levels of clarithromycin in patients treated with multidrug regimens including rifampin or rifabutin for Mycobacterium avium-M. intracellulare infection.

http://www.ncbi.nlm.nih.gov/pubmed/7876634

Red

[rowingmom]

DD10 (70 lbs) is also taking biaxin (250mg BID)/rifampin (150mg BID). She has been taking these for about a year now for lyme/bart, and we added pulsed tindamax a couple of months ago. Whenever she is on the combination she does well. Pain resolves, and PANS reactions subside. Whenever one or the other is removed and covered with herbal/homeopathy (A-Bart, A-L) for longer than two months everything returns. It seems as though both are required. Thanks Red for the article links. I will be heading to the LLMD with those.

[red]

DD10 (70 lbs) is also taking biaxin (250mg BID)/rifampin (150mg BID). She has been taking these for about a year now for lyme/bart, and we added pulsed tindamax a couple of months ago. Whenever she is on the combination she does well. Pain resolves, and PANS reactions subside. Whenever one or the other is removed and covered with herbal/homeopathy (A-Bart, A-L) for longer than two months everything returns. It seems as though both are required. Thanks Red for the article links. I will be heading to the LLMD with those.

To take this a step further in understanding the role of rifampin you have to look at the CYP3A4 cytochrome in the liver. Rifampin is an "inducer" of CYP3A4. Which means as rifampin is metabolized it causes an increase of CYP3A4. Then along comes a drug that needs CYP3A4 to be metabolized. But there is so much CYP3A4 as a result of induction by rifampin that the next drug gets super metabolized in the liver and most of it never makes it into the bloodstream. It is sort of like using O2 on a fire.

Red