Ask the Pharmacist Q2 2019

Questions submitted by readers and answered by the CLL Society Medical Advisory Board

Remember that we cannot give medical advice and any suggestions should be reviewed with your treating doctors.

By Thomas E Henry III, MBA, RPh, CPh

I am a 43-year-old female with heavy periods on ibrutinib. I am low on iron with a hemoglobin of 10.7. When I take over the counter iron, I get constipated and nauseous. Any advice?

Here is the answer from Tom Henry, our pharmacist expert.

Your hemoglobin level may not be a result of iron deficiency, CLL can result in reduced hemoglobin (Hgb) levels as the lymphocytes crowd out red blood cells (anemia) and correspondingly the Hgb drops.  Ibrutinib does result in some blood thinning which may account for the heavier menstrual flow.  Heavy menstrual flow alone can cause many women to be anemic so one would expect that with Ibrutinib this could be worse.  I would definitely discuss this with your provider if you haven’t already done so. 

Here are some suggestions if you continue to take the iron:

• Switch to slow release formulation of iron which will delay the dissolution of the product and reduce the incidence of nausea caused by irritation of the iron salts on the stomach lining. The brand name for this product is SlowFe but there are generics available.  I order this for myself on Amazon for about $3.00 per 100 tablets.  I would recommend two tablets a day taken with meals or food which further reduces the stomach irritation.
• To reduce the constipating effects of iron therapy, I would recommend one of two products that only work in the intestines and are not systemically absorbed. These products soften the stool by increasing the amount of water in the bowel.  The capsule form is docusate sodium (Colace) which comes in 100mg caps.  I would start with one twice a day at the time of iron, and if needed, can increase up to 3 capsules twice a day.  The other product is polyethylene glycol (Miralax), that is mixed with water.  For this product, I would start with one scoop daily and taper up to desired effect.  With both of these products, drinking plenty of water is important and this is also important with Ibrutinib.  Also, both products are over-the-counter.
• If you are not already doing so, I would recommend that you take at least 500mg of Vitamin C at the same time you take the iron. Oral iron is poorly absorbed from the gut and the Vitamin C increases absorption.

 

I was told to avoid antifungal medicines with my venetoclax for my CLL. Does that include the creams for “athlete’s foot” or only the pills?

You are correct, there is a warning to avoid the antifungals that end with “azole” orally.  This is because the antifungal and the Ibrutinib are metabolized by the same enzyme.  The antifungal has higher affinity for the enzyme and “crowds out” the Ibrutinib metabolism.  The result is that Ibrutinib accumulates in the blood and causes increased side effects and toxicity.  While the level of systemic absorption is small, thereby reducing the risk of an interaction, I would make the recommendation to try the topical antifungal tolnaftate first as there are no drug interactions associated with this medication that is available over-the-counter.  If that fails to give the response you need, I would suggest talking to your CLL team before using any of the other antifungals topically.

 

---

Thomas Henry is a Registered Pharmacist and CLL Patient. He is President and Senior Consultant for Burlington Consulting Associates, a company that provides consulting services to health systems nationwide. Tom is a CLL Society Medical Advisory Board member and strives to educate other CLL patients through his blog https//www.cllpharmacist.com. He has a forty-two-year career in pharmacy and has served as Chief Pharmacy Officer at two Top-15 Comprehensive Cancer Centers, Moffitt (Tampa, FL) and Roswell Park (Buffalo, NY).