My Side Effects of Tafinlar and Mekinist - Fevers

Fevers have been my biggest obstacle so far. They are also the most common side effect. 

My fevers didn't start until after I had been taking both medications for 2 months. I started Tafinlar and Mekinist on August 7, 2022 and fevers began around Oct 4, 2022 to our surprise.

I was told most side effects would start in the first month or two, rarely after. So it wasn't expected. 

LABS

During the the first few episodes of fever, we paused the medications and did a full lab workup including cultures. This helped us know for sure if there was an infection causing the fevers or not. Everything was negative. It was just the chemo. But it's good to check. 

NOT MUCH INFO

When the fevers first started, we tried to find information online about these side effect fevers. But it was difficult to find direct patient experiences. 

We wondered things like:

- How high did fevers get?

- How long did they last?

- Did they go away or did you need to pause chemo?

- Did they keep recurring?

- How did they manage them?

- Were they fixed somehow? 

So we thought we would share my experience in case it helps. 

FIRST FEVER

When my fevers first started, they were lower and lasted fewer days. For example, in early October, they were around 100.4 and easily diminished when we paused chemo for 3 days or so.

It may be good to note that along with all raised body temperatures, no matter the number, I always get very chilled (shivering bad) and lots of body aches. It's very uncomfortable to say the least. 

PROTOCOL

The protocol is that once my body temperature reaches over 100.4 (a true fever) we pause chemo in order to let the fever reduce. Then we restart it once I am fever free, with no Tylenol, for 24 hours. 

In my case they only allowed me up to 3000mg of Tylenol per day. That was tricky since it only lasted 3 to 4 hours for me. 

MORE FEVERS

After the first fever or two, my fevers tended to go well above the 100.4 and quickly, often hovering around 102 degrees and at times increasing up to 104 degrees. They often kept climbing for a few days, even after pausing chemo. Perhaps due to half lives and inflammation.  

LOWERED THE DOSE

After this happened the first couple of times, my doctors lowered my dose of Tafinlar and Mekinist. 

NEW DOSE 

My new dose of Tafinlar was 2x50mg instead of 2x75mg. Twice per day. The new dose of Mekinist was 3x0.5mg instead of 1x2mg. Once per day. 

DIDN'T WORK 

Unfortunately the fevers kept happening despite the lowered dose of Tafinlar and Mekinist. We realized we just couldn't get any control over them. 

In fact, they were higher and lasting longer. Once, after pausing chemo, the fevers increased to over 104 and lasted over 8 days. 

Once I'd resume the medications, I'd only be back on them for 4 to 5 days before fevers would begin again. This resulted in many days off of the chemo.

So it was really becoming an issue. 

ADDED STEROIDS 

In mid-November, about one month after lowering the dose of Tafinlar and Mekinist, my doctor decided to try adding 10mg of steroids (Prednisone) daily in hopes of controlling the fevers. 

We had noticed that many doctors wrote online about steriods helping their patients get past these fevers. In fact, here is a video where an Australian doctor talks about using steroids for this purpose. 

However, a couple of weeks later, my fevers broke through the steroids. Not at an extreme temperature but around 101 degrees.

INCREASED STEROIDS 

So we paused for 3 days, then restarted and increased the steroids to 15mg once a day in December. See my timeline. 

This seemed to do the trick. However after 12 days, body temperatures were rising again. Along with it, as always, came massive body aches and chills. 

However it took 3 days to reach 101 degrees, a temperature that requires pausing chemo. 

BREAKTHROUGH 

Before we could report it or pause the medications, the fever reduced on its own for the first time. Back to a normal body temperature of 97.5 to 98 degrees. This was on Christmas day. 

It was a breakthrough. 

My body temperature remained at a normal temperature with only 2 known times that it reached 99 degree readings since then, so far. It's now January 2, 2023, day 25 after restarting chemo this time. That's a record. 

LENGTH OF STEROIDS 

My doctors were not too keen on me being on steroids super long term. The idea is to take them only as long as necessary. Other doctors online seem to say the same. The Australian doctor that I linked to above says 3 to 5 months. Then you will want to taper off of them once they are no longer needed, and see how the body adjusts along the way. 

It seems with this method, it allows the body to get used to the medications and the fevers are no longer an issue after a while. I hope that is my case and I can begin to taper off soon. 

However, in some cases you may taper off only to find the fevers returning. In that case, you'd extend your steroid time. 

DOSE OF STEROIDS 

The doses given seems to vary between 5 and 25mg most often. But we are no medical experts and are only sharing our experience and things we read. So please look into this and follow the advice of your doctor. 

My dose started at 10mg and then doctors increased it to 15mg after about 3 weeks. 

WORTH NOTING

It may be worth noting that in our research, it seems the body is typically most inflamed between 3 and 4am. And, in fact, this was always when my fevers were at their highest. 

I realized that if steroids last 16 to 20 hours, they were wearing off by that time slot when I took them at 10am. So I started taking the steroids at night around 10pm so they covered that time period rather than wearing off around that time. This helped a lot. 

However, I could only tolerate this at the 10mg steroid dosage. Steroids can keep you awake at night by messing with your circadian rhythm. At 15mg it was interfering more with my sleep.

Also, I did try to push through the fevers without pausing the chemo, for a few days once. But they only got worse. Higher and lasted longer even after pausing. And for 3 weeks after I was extra tired and achy, even after the fevers finally stopped. 

So that did not work at all. 

*I was off of chemo for a total of 28 days in 2022, between Oct 4 and Dec 5, due to fevers.