Ask the Pharmacist Q1 2018

My dad is never sure whether he has a viral or bacterial infection, and always takes antibiotics when he’s sick (he has CLL). What are the potential side effects of this?

First of all, Thanks for being part of your Dad’s support network on his CLL journey!

You are right to be concerned about his use of antibiotics whenever he’s sick without knowing if it is a viral or bacterial infection.  The overuse of antibiotics is a major issue facing the healthcare system, because the more times a bacteria is exposed to an antibiotic the more chance that the bacteria will mutate to protect itself.  We call this antibiotic resistance.  Essentially if a bacteria becomes resistant it will no longer be killed by an antibiotic that used to be effective.  What we are finding is some bacteria are becoming resistant to multiple drugs and then we lose the ability to fight that organism.

Another issue is that antibiotics can kill the good bugs along with the bad, potentially leading to gastrointestinal issues ranging from mild diarrhea to dangerous bacterial overgrowth in the intestinal tract.

Also as with most medications, antibiotics can have mild or even serious side effects. And recurrent exposures can increase the odds of allergic reactions.

Part of the difficulty in differentiating is that viruses and bacteria can both cause some illnesses.  Bronchitis, Ear Infections and Sinus Infections can be caused by either a viral or bacterial infection.  There are also instances where an infection can start off as a viral infection but because the increase in secretions in the nasal passages or upper respiratory tract form a natural “breeding ground” for the bacteria to take over.  This is caused a Secondary Infection.

Patients should rely on their general practitioner to distinguish between a viral and bacterial infection.  We encourage a “wait and see” approach to initial signs of infection to determine if the cause is viral or bacterial.  Some triggers for when to see a medical provider, because the culprit is likely bacterial, are:

• Symptoms that last more than 10 days
• Recurring fevers
• Shortness of breath
• Excessive yellow, green or beige mucus
• White patches at the back of the throat
• Severe coughing
• Any urinary tract infection

That said, the threshold to use antibiotics in CLL patients may be lower due to our impaired immunity and the risk of infections quickly getting out of control. When a CLL patient gets sick with an infection, it is critical to get a medical opinion about the appropriate management.

I have one further suggestion to make and that is that you might want to speak to your Dad’s general practitioner, about your concern of potential overuse of antibiotics and see what the response is you get.  If they plan to continue to supply prescriptions when they may not be justified or puts refills on prescriptions that allow you Dad to “self-diagnose” and treat you may want to explore another provider.

I’ve been told that I can’t drink grapefruit juice with my medication for CLL? Why is that? Is that true for all drugs?

Many drugs are metabolized or broken down by enzymes, particularly in the small intestine.  Grapefruit juice as well as whole grapefruit and Seville oranges (used to make marmalade) block the action of the enzyme CYP3A4.  If the drug you are taking is also metabolized by CYP3A4 then less is metabolized and more enters the blood stream.  When more of the drug enters the blood there is more likelihood of an adverse consequence or side effect.  Not all medications are metabolized by CYP3A4 so not all medications require that you abstain from grapefruit products or Seville oranges.  The three most common CLL oral medications, ibrutinib, venetoclax and idelalisib all carry warnings to avoid grapefruit and Seville oranges.  Many other medications including some cholesterol lowering “statins”, cardiac medications, some immunosuppressants, psychiatric drugs, HIV medications and even Viagra carry this warning.

Does it make a difference if I take my meds in the morning or in the evening?

Of the three most common oral CLL medications, idelalisib is given twice daily so essentially both morning and evening.  The manufacturers of ibrutinib and venetoclax do not specify a specific time (just approximately same time every day).  From a practical standpoint morning administration is preferred because all products recommend that each dose be taken with a full glass (8-10 ounces of water.  Further to limit side effects and toxicities, all three recommend larger than average fluid intake throughout the day  with idelalisib at 2 to 3 quarts a day (64-96 ounces), ibrutinib and venetoclax 6-8 glasses (56 ounces total).  By taking the dose in the morning it is possible to avoid late evening fluid intake and the corresponding sleep disturbance of multiple trips to the bathroom.

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Thomas E. Henry III, is a fellow CLL patient and a Registered Pharmacist licensed in 23 states and a Consultant Pharmacist in the State of Florida. He serves as Chief Pharmacy Officer at Moffitt Cancer Center, in Tampa, FL, where he oversees inpatient, outpatient, specialty and research pharmacy services.  In addition, he is the President and Senior Consultant of Burlington Consulting Associates a firm that specializes in hospital pharmacy management consulting.

Originally published in The CLL Tribune Q1 2018.