High Dose Vitamin D: Is it safe?

I am on high dose Vitamin D. I take 1 pill a week for 8 weeks. My vitamin D level was extremally low. I also take a regular dose of it in gummy form.

Has it helped either with fighting your underlying illness or in alleviating "Chemo Brain" or "Chemo Hand-Feet Syndrome?"

Watch for vitamin D toxicity with mega doses, the calcium level should be carefully monitored. Vitamin D toxicity is slow to resolve since the liver stores vitamin D, could take months.

Bread crumb trails can be dangerous - you don't post any citations for your question - where are you obtaining this information?

What does your doctor say?

My doctor is unhelpful (for instance never mentioning the side effects of chemotherapy) and saying to just keep taking whatever vitamins I've been taking when asked.
I've learned more from the nurses taking care of patients. That's why I'm searching for answers elsewhere.
It turns out that the "high dose" vitamin D I still have on hand is meant to be taken once per week.

This page from Cleveland Clinic is still in my browser library so is probably where I was reading that vitamin D deficiency can lead to muscle weakness, as well as some of the other symptoms I'm experiencing.
https://my.clevelandclinic.org/health/diseases/15050-vitamin-d-vitamin-d-deficiency
Notice, too, that one of the predisposing conditions to vitamin D deficiency is that your body isn't properly absorbing or using it (I am taking Creon but it's hard to tease out from https://www.creoninfo.com/ how Creon affects vitamin D absorption, although the page does offer to sell you their brand vitamins.
I will ask my doctor at my next appointment to have my vitamin D level measured.

In yet another example of silo-ization of medical care in my community, this test has already been "turfed off" to my PCP.

How much is your high dose? What are your levels now?

I have not yet had a test for my current levels of vitamin D.

My "high dose" vitamin D3 (which I was NOT taking at the time I did have a vitamin D level measured in September 2022) is 50,000 IU and is directed to be taken WEEKLY.

Vitamin D is commonly referred to as the Happy Supplement.I went from living in FL, cycling 100 miles a week to mountain life in NC where we spend winters indoors. I started taking 10,000 units of Vitamin D several years ago daily and have my levels checked yearly, which are perfect As a side note, I have not had so much as a sniffle in 3 years as I add Zinc C Mag and several other supplements daily