Obviously chemotherapy is going to make you feel unwell, but there is a huge difference between unwell and the symptoms listed above. I can’t speak for other chemotherapies, but 5FU and Capecitabine should have mild side effects. My mom’s oncologists said that she wouldn't be throwing up and would feel fatigued but still able to go about her day. With these low expectations in mind, we opted to go through with chemotherapy after my mother’s successful surgery (She was diagnosed with stage 3 colon cancer and after removing her tumor found cancerous cells in 2 of her lymph nodes)The oncologists said that the safest choice was to go through with the chemo and we did.
At first my mom was fine. Her first dose of chemo was intravenous 5FU and then she went to oral Capecitabine twice a day. During the first few days she was tired and had diarrhea but after day 4 she was in bed all day, could hardly do anything, had bad diarrhea, and would get intense headaches which caused her to throw up. We called the oncology team and the nurse practitioner just told us to get her Imodium for her diarrhea and a wash for her mouth which started to develop a sore. The team claimed they were not worried and offered IV fluids. Another thing to mention is that around day 6 or 7 my mom was verbalizing her discomfort and saying things like, “this is poisoning me” and “I feel like I'm dying.” I bring this up because you have to listen to the patient. When we voiced the symptoms my mom was having they made it seem like what she was experiencing was normal and that it’s just the way chemotherapy goes. Despite hounding them on the portal and updating them on every development they continued to downplay our fears.
On day 7 we spoke with the oncologist directly and he said that she was having a bad reaction to the chemo and that she might have been overdosed from the beginning. He then decided to cut down her medication by half per day and recommended getting more IV fluid from an outpatient clinic that weekend. The morning of day 8 my mom was so sick that my dad realized something was very wrong and stopped the chemo medication all together. We drove my mom to urgent care on Friday to get some tests done and receive more fluid. She was monitored for a few hours and then they told us she could come home as her vitals were stable and she was feeling better. They were going to do a stool test to figure out her diarrhea issue but they ultimately decided against it. Another thing to watch for, IV fluids can make sick patients feel temporarily better and create a false sense of confidence. So we brought her home that weekend but on Monday her diarrhea got really bad and we rushed her right back. After finally doing a stool test they realized she had C-Difficile, a very bad bacterial infection in her gut which most likely came about from the chemotherapy destroying competing bacteria.
After getting this news we felt better because a) her cause of her diarrhea was diagnosed and b) she was no longer on chemo so we thought it shouldn't cause any more problems. However after three days in the hospital, she was not getting better and her blood results showed that her white blood cell count was close to zero and her heart rate was consistently in the 130 beats per minute range. The oncologist then realized that my mother was having severe chemo toxicity and ordered Vistogard to flush the chemotherapy out of her body. She was moved to the ICU and was placed under supplemental care plus antibiotics to treat her C Difficile. That same night then Vistogard arrived and my mother took her first dose which was extremely hard to take down given her severe mucositis. It is important to note that Vistogard only has been clinically proven to work if taken within 96 hours after the last dose of chemotherapy. My mother was past that time frame and I was very worried that the medicine would not work. Fortunately, after the first two doses my mothers vitals started to improve. My mothers surgeon saw her after the first 2 doses and told us that my mother would have a long recovery but that would be okay.
Ultimately, my mother was in the hospital for 18 more days which were very taxing on her body. Even with the Vistogard the mucositis and GI infection combined took a big toll. Doctors couldn't tell whether or not her bowel inflammation was from the bacteria or the mucositis and made it clear that until her diarrhea subsided and she could start taking down liquids that she would not be released. Throughout the 3+ weeks she was in the hospital in total her white blood cells went to 0, her red blood cells/platelets/hemoglobin fell to dangerous low levels, she received a blood transfusion, and was given a PICC line for nutrition. After leaving the hospital and resting at home my mother lost all her hair, was on nutrition bags for three weeks, and got a pulmonary embolism (clot) for which she was put on blood thinners. The clot caused extreme discomfort and was not diagnosed for days because we thought it was muscular. Thank God my mother recovered fully but unfortunately that is not the outcome for the thousands of people who die from chemo toxicity due to DPD deficiency.
In summary, receiving a DPD deficiency test before taking chemotherapy is simple, quick, and relatively inexpensive. As you can see from the story about my mother, the consequences of chemo toxicity can be life threatening, require intensive care and monitoring for months, and quite traumatic for the body and mind of the patient. Such trauma can be avoided by a simple test and you need to make sure that before taking FLUOROURACIL (5FU) or CAPECITABINE chemotherapy make sure you get tested for DPD enzyme deficiency (dihydropyrimidine dehydrogenase).