Antibiotics with Venetoclax

[difor29]

Hi all! I’m on Venetoclax and Rituxan for NHL. I need to go to the dentist. I think it’s a cavity but my luck, a root canal. What is a good antibiotic to take that does not interact with Venetoclax? I’m not getting any answers from my oncologist. All I was told was that I have to stop Venetoclax 3 days prior to the procedure and 3 days after. I should also mention that I am allergic to penicillin. Thanks!!!

[Ladylin151]

Your dentist and your pharmacist should get together on this. They are the experts.

[AussieNeil Administrator]

With respect to antibiotics that could interfere with venetoclax/Venclexta drugs.com/drug-interactions... shows very few antibiotic interactions.

I've not heard of withholding venetoclax around surgery and there's no mention on the official website venclexta.com/

Withholding is done with BTKi drugs, acalabrutinib, ibrutinib, zanubrutinib, etc, because this class of drugs can adversely affect the clotting process, increasing the bleeding risk post surgery. That's due to the off target impact on the tyrosine kinase inhibitor found in platelets. You might want to check with your oncologist as to why the recommendation in your case. Perhaps you've a particularly low platelet count?

Neil

[DRM18 in reply to AussieNeil]

Hi Neil,

I remember, when I was on V (for a year or so), being told to avoid the fluoroquinolone class of antibiotics.

Was I misinformed?

--Dave!

[AussieNeil Administrator in reply to DRM18]

Hi Dave,

Drugs.com specifically lists the fluoroquinolone antibotic levofloxacin, but not ciprofloxacin. However if you check ciprofloxacin, drugs.com notes "Using venetoclax together with ciprofloxacin is generally not recommended. Combining these medications may significantly increase the blood levels and effects of venetoclax."

The issue is that venetoclax relies on the CYP3A4 enzyme and P-glycoprotein (P-gp), to clear it, so you need to reduce the dose or monitor for safety via blood tests when taking drugs that inhibit CYP34A or P-gp.

Difor29 pdr.net/Mobile/Pages/drug-s... lists more information on potential antibiotic interactions. Perhaps a hospital pharmacist would be a good resource given your oncologist's lack of support. Per the pdr website, dose reduction, rather than holding venetoclax may be all that is necessary. For some antibiotics, that's only recommended during the initiation and ramp up phases.

Neil

[difor29 in reply to AussieNeil]

All my bloods are great! Onco just told me that they want me to pause Venetoclax like I mentioned just as a precaution. But I’m not getting any answers as to what kind of antibiotics to avoid. The only antibiotic I can tolerate is the ZPACK

[AussieNeil Administrator in reply to difor29]

I couldn't see azithromycin mentioned in either of the previously mentioned drug interaction sites. Also per pubmed.ncbi.nlm.nih.gov/302...

Conclusions: The modest changes in venetoclax exposures when given with azithromycin indicate that no dose adjustment would be needed when venetoclax is coadministered with azithromycin or other drugs with P-gp inhibitory potential. Azithromycin represents an alternative to other antimicrobial agents with higher potential to alter venetoclax pharmacokinetics such as clarithromycin, erythromycin, and ciprofloxacin.

Neil

[difor29 in reply to AussieNeil]

I’m thinking they are being very cautious with me because I’m on a clinical trial?

[AussieNeil Administrator in reply to difor29]

Maintaining good oral health is also important, particularly when you are at risk of neutropenia. Venetoclax and to a lesser extent rituximab are both renown for causing neutropenia. You don't want bacteria getting into your blood without prophylactic antibiotics when you are at risk of becoming neutropenic.

I was informed ages ago after an emergency hospital admission to treat pseudo membranous colitis that came on quickly after a couple of antibiotic doses for an ear infection, that I shouldn't take penicillin antibiotics. My haematologist prescribed a high dose of amoxicillin to be taken an hour before any dental work, including teeth cleaning by the dental hygienist. See if you can get in contact with a pharmacist supporting your trial to confirm a amoxicillin prophylactic for you before your dental appointment.

I found out just a few years ago that I can take penicillin based antibiotics and that in many cases this advice about avoiding penicillin antibiotics is incorrectly given. In my case, I suspect a C difficile infection, brought on by the antibiotic wiping out protective gut bacteria, caused the colitis. This happened about a year after I needed some powerful IV antibiotics to treat peritonitis from a burst appendix - on a weekend naturally. So I suspect resident C diff had developed resistance to the earlier antibiotics.

During watch and wait I had chronic, often severe neutropenia, resulting in several hospital admissions for IV antibiotics to treat febrile neutropenia. Avoiding penicillin antibiotics made treatment challenging, so it was possibly a life saving finding for me, knowing that I could be prescribed a much wider range of antibiotics. So plesse get your penicillin allergy verified.

Neil

[difor29 in reply to AussieNeil]

Thank you Neil. I just wish someone would call me back. I’ll try again tomorrow.

[edelweiss]

I am on venetoclax and also happen to be allergic to Penicillin. I just had a teeth cleaning and take clindamycin 600mg one hour before any dental procedure. My dentist prescribes the antibiotic.

[prbs2707]

I was on obinutuzumab & venetoclax for a year. I finished V a month ago. During treatment a few months ago I had to have root canal. I was not told to stop V but I was (throughout O&V treatment) on a mild antibiotic Co-trimoxole which I took twice a day every Mon wed and Fri. Dentist was aware and was ultra careful and rang me several times to check I was OK. She was ready with antibiotics if I developed any problems. She didn't anticipate any and there weren't. Everything was fine. I did also take a twice daily antiseptic mouthwash which probably helped. I would discuss it with the dentist she/he is key so needs to be fully aware of your situation in case of any infections. But for me it all went fine and I felt confident things were in place just in case. Good luck with it all. Patrick

[Pinecrest]

I’m also allergic to penicillin. I take 400 mg Venclexta and 400 mg twice a day of Acyclovir for 2 years.

[difor29 in reply to Pinecrest]

I also take the Acyvlovir and 800 mg of Venetoclax.

[difor29]

Thanks for everyone’s input! I spoke to my oncology nurse. If it’s just a straight forward cavity, I can stay on the Venetoclax and just get an antibiotic. Preferably azithromycin or clindamycin. If it’s a more complicated procedure like a very deep cavity or root canal, I go off of the Venetoclax. I’m going tomorrow for an X-ray. No matter what it is, I’ll have my dentist contact my oncologist before he proceeds. Diana