B12 deficiency with mCRPC

I am so sorry to hear that. Can you ask your doctor to give him b12 shot ? They do have it at disposal, I know that since I asked my husband's doctor for B12 shot when he had shingles. Shots have immediate effect and it is shame that they are not offered regularly in the States, in Europe it is standard practice.
We also use B12 sublingual tablets as supplements :https://www.amazon.com/dp/B00NV5UTIE?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_4

As we age our guts have trouble absorbing B12 from food and sublingual administration gives potentially better results. Do not forget to put tablet under the tongue and let is dissolve slowly in the mouth.

Wishing you the best of luck 🌺

Thank you. I will see what the labs show next week. I have learned you definitely have to be pushy sometimes.

B-12 has 2 sources. With intrinsic factor produced in the stomach certain bacteria at the end of the small intestine fabricates it. Those on acid reducing medicines are at greater risk of not producing enough. BTW: the definition of a vitamin is a necessary chemical needed to facilitate various biochemical pathways. A vitamin may be produced in the body but inadequate in the required amounts and must be supplemented. Some vitamins must come totally from dietary sources such
as ascorbic acid (VitC) is a vitamin only for humans and some other mammals. For all other species it can be produced in adequate amounts 'endogenously'. Cyanocobalamin was a administered by intramuscular injection. It was a favorite treatment of the medical profession before WW2. 'Those who 'topped off'
the shots with amphetamines were pejoratively referred to as 'Dr. Feel Goods' The sublingual oral methemoglobin is far more convenient,

From my experience cancer doc's are only interested in treating the cancer not the whole person. Side effects be damned. Anemic? No comment. Rectal bleeding during radiation? Must be the way you wipe. Bladder urgency to the point of blowing up on the table? Empty, drink and get back on that table as I need that $5K today. Receptionist wanted to know if I wanted 5 additional sessions? I said sure as long as you paid me the $5K per session. I hated my radiation team and will find another one if needed.

So very true in most cases. You definitely have to be your own advocate. None of my cancer doctors mentioned bone density, exercise, vitamins,etc etc. Even here at Mayo. I have found it true of other specialist too. They totally focus on their specialty and ignore the rest of the body.

My PCP is like the head coach of my football team. We communicate by messaging about issues I'm having, unless a telehealth or an in person visit is warranted, then she communicates with the specialists, the figures out next steps to a resolution, sees that they are implemented then follows up to check on the results. I feel great PCP is essential!
Bill

I just searched on B12 affect on PCa on a couple chatbots. In a meta-analysis it looks like high levels of B12 don't reduce or slow PCa; most studies show no effect, but a couple studies show that B12 could worsen aggressive PCa a bit (OR 1.17 and one study OR 1.5ish, I think). I was low a year ago and started taking it. My PCa persists so I'm going to do a blood test and to be safe, will likely reduce or stop taking B12 myself. It doesn't look like it's a huge factor but my rule now is that I won't take any supplement or food, even if some studies show benefit, where respectable other studies show that it may make PCa worse (i.e Vit. E, selenium in brazil nuts, etc). There's a lot they don't know about diet, vitamins, and supplements still, so I'm trying to play it safe. And interactions are really hard to predict.

Thanks for that information. Were you feeling extreme fatigue when you started the B12 supplements? And were they helpful?