Dosing for Metformin for prostate cancer

[Nigu-1]

I am sort of new to this site and have a question about dosing for Metformin for mestastatic prostate cancer. I am on Lupron now and am taking 50 mg of Metformin two times per day. I was given a Rx for it by my naturopath as my oncologist would not prescribe it. I am wondering if I should be taking a higher dose.

[kaptank]

For a decade or so I have been taking 2g (2000mg) per day. That is about the max. No side effects. Good control of sugar and insulin: important in managing PCa. 100mg won't do much. I think your regular health practitioner/general practice doctor is more likely to prescribe, particularly if you have any symptoms toward prediabetic or just want to prevent such problems. An oncologist will generally think its not in their pay grade.

[Nigu-1 in reply to kaptank]

Thanks for the info

[GP24]

If you increase the dose you often get diarrhea at first. So you could increase to 500 mg, stay on that dose for two weeks, then increase to 1000 mg and so forth until you reach the max. dose of 2000 mg /day.

However, there is no definite proof that Metformin helps against prostate cancer yet. We have to wait for the results of the STAMPEDE trial, arm K.

[6357axbz]

I concur with GP24. I take 500mg twice a day with food. Prescribed by my GP for off label use with PCa. No SEs.

[pjoshea13]

I believe that this Swiss study finally convinced Dr. Myers to recommend 2,000 mg / day:

pubmed.ncbi.nlm.nih.gov/244...

The paper certainly caused me to increase my dose.

I take 2 x 500mg twice daily.

For someone not currently using Metformin, it is best to start at 500mg for a couple of weeks & move stepwise to the desired dose.

-Patrick

[Nigu-1 in reply to pjoshea13]

Thanks

[Nigu-1 in reply to pjoshea13]

Thanks for the link to the pubmed study

[LearnAll in reply to pjoshea13]

Thanks Patrick for this valuable info. What is your opinion about people like me who do not have diabetes (HbA1c=5.6). Does it still help to take metformin 2000 mg a day ?

[pjoshea13 in reply to LearnAll]

For most of the Metformin-PCa studies, we can assume that cohorts were primarily diabetics, with maybe some pre-diabetics. The question being whether one could extrapolate to non-diabetics & even those with normal insulin sensitvity (no insulin resistance).

From what I have read, there are various ways in which Metformin may benefit us - i.e. in addition to the insulin issue. There seems to be benefits in cancers unrelated to insulin.

Like you, I'm not an obvious choice for Metformin, but I'm staying with it.

Men diagnosed with PCa tend to have more symptoms of the Metabolic Syndrome [MetS] (& that only worsens with ADT). I think that there is a case for starting men on Metformin at diagnosis, without regard to MetS.

-Patrick

[GP24 in reply to pjoshea13]

This study included CRPC patients only and showed just a small benefit in my opinion. If the result applies to hormone-sensitive patients too is unknown.

[HOPEFULSPOUSE in reply to pjoshea13]

Thanks for this Patrick.

My husband's Swiss oncologist had him taking 2000 mg. (Ben Pfeifer - MD / PhD, former head of prostate at MSK).

[j-o-h-n in reply to HOPEFULSPOUSE]

Just to set the record straight Dr. Ben L Pfeifer was never "Head of Prostate at MSK".

See Biography below: (Including an extensive search by me)...

Ben L. Pfeifer, M.D., Ph.D.

Professor and Director for Research & Development, Aeskulap-International, Switzerland

Portrait Professor Ben L. PfeiferSpecialties and Interests:

Anaesthesiology & Intensive Care Medicine, Cancer Immunology, Integrative Oncology

Education and professional life in Germany from 1968-1984:

Medical Studies and Specialty Training at Humboldt-University Berlin, Germany; Senior Consultant Physician at Department of Anaesthesiology / Intensive Care at Humboldt-University Medical Centre; Senior Consultant Physician at Philipps University Marburg, Germany; Medical Director at Cancer and Pain Treatment Centre, Bad Mergentheim, Germany.

Education and professional life in USA from 1985-2000:

Visiting Professor and Fellow at University of South Florida, USA; Medical Director of Immune Therapy Clinics of Playas de Tijuana, Mexico; Visiting Professor at University of California, San Diego, California, USA; Second Specialty Training at University of Kentucky, Lexington, Kentucky, USA; Assistant Professor, Director for Clinical Research and Attending Physician in Department of Anaesthesiology at University Medical Centre of University of Kentucky, Lexington, Kentucky, USA.

Education and professional life in Switzerland from 2001-2014:

Senior Consulting Physician at the Department of Oncology of Aeskulap Hospital, Brunnen, Switzerland; Director for Clinical Research at Aeskulap Hospital, Switzerland; Director of Research and Development at Aeskulap-International, Lucerne, Switzerland.

Scientific Activities:

76 publications in peer reviewed medical journals

1 book (first text book on “Integrative Oncology”); several book chapters in other medical text books

56 presented papers at national and international medical conferences

Invited lecturer at the Academy of Sciences in Germany, Russia, USA and Poland

Honours:

Humboldt-Prize

Immunological Research Prize

Good Luck, Good Health and Good Humor.

j-o-h-n Tuesday 05/26/2020 8:05 PM DST

[HOPEFULSPOUSE in reply to j-o-h-n]

Thank you J-o-h-n,

I stand corrected.

Impressive bio just the same.

But for me and for my husband, most impressive is his kindness and humility.

[j-o-h-n in reply to HOPEFULSPOUSE]

I'm glad that you both like him because that's what counts... I like them kind, with humility and definately with a sense of humor. Stay well, stay safe and of course -

Good Luck, Good Health and Good Humor.

j-o-h-n Tuesday 05/26/2020 10:19 PM DST

[Boywonder56 in reply to j-o-h-n]

Tuff crowd......

[j-o-h-n in reply to Boywonder56]

Yep they sure are, especially the ones born in 1956......

Good Luck, Good Health and Good Humor.

j-o-h-n Friday 06/05/2020 5:54 PM DST

[Nigu-1]

Yes I ment to sy 500 mg.

[Tall_Allen]

You should not be taking it at all based on our best data, unless you are diabetic.

ascopubs.org/doi/10.1200/JC...

urotoday.com/conference-hig...

meetinglibrary.asco.org/rec...

It seems that the previous observational studies were flawed because diabetic men received fewer biopsies for elevated PSA:

jamanetwork.com/journals/ja...

[edgeh in reply to Tall_Allen]

Thanks for the redirects. I read previous posts about the possible benefit of Metformin so took 500mg each day for a month then increased the dosage to 850mg per day. I started having leg cramps and constipation. On reading about secondary adverse effects l also discovered it should not be taken with Amlodipine. So the redirect notice gave me confidence in stopping Metformin. Except for vitamin d3 there seems to be no advantage in searching for alleviation in supplements, vitamins etc., but please correct me if l' m wrong.

[Tall_Allen in reply to edgeh]

People post all kinds of studies on this site. Most aren't worth the paper they're printed on - to the credit of the people who wrote those studies, they never meant for their studies to be abused like that.

As for D3 -- Here ya go:

pcnrv.blogspot.com/2018/07/...

[edgeh in reply to Tall_Allen]

Thank you Tall_Allen. As with anyone who has cancer we search for any possible remediation. Am l correct therefore, ìn saying that a good diet supplying necessary vitamins etc., is sufficient and that supplementation has no effect according to studies, but supplemention could actually cause harm?

All the voices on healthunlocked are balm to our suffering and l thank you for your courtesy, patience and knowledge.

[Tall_Allen in reply to edgeh]

Absolutely correct. I am not as unsympathetic as I might appear. In fact, I still have a large drawerful of supplements from when I was first diagnosed. I definitely understand the desire to wrest any modicum of control when so much control has been stolen from us. It feels less helpless- like at least we are doing something.

There may be supplements that help. Sulforaphane, for example, looks good in early trials. But until long-term controlled trials are completed, we have no idea what their true efficacy and toxicity is. We can be certain that no supplement has just one effect. Biochemistry doesn't work that way. There are always interactions with other drugs we take, with liver enzymes, and with unforeseen effects on other organs and with biochemical pathways. With supplements (even the name brand ones) we have no idea of the quantity and quality of what's really in the bottle.

On the other hand, prostate cancer is a serious disease that alters biochemistry. That's why it's more important than ever to fully understand exactly what every drug (and supplements are drugs) does before we take them. Our bodies have evolved, and our microbiome has coevolved, over millions of years to extract the nutrients and micronutrients we need from the foods we eat. That means our health is optimized by a balanced and varied diet, with calories adjusted for age and activity level. The best diet seems to be: Highly colored fruits and vegetables (especially cruciferous vegetables), varied protein sources, fats from vegetable sources, high in fiber, low in processed foods.

[edgeh in reply to Tall_Allen]

Thank you so much.

[tonmead]

I'm on the stampede trial , arm K. Have been for three years. the dose is 850 mg twice a day(1700 mg a day in total). I was not diabetic or pre diabetic and am still not. do occasionally get diarrhoea. PSA stayed at 0.08 for around 2years. My last 3 bloods have shown increase to 1.2, so Dr. put me on 50 mg of bicalutimide, latest blood results coming tomorrow. I've had no official results of this trial, but very few side effects for me. I'm also on three monthly injection of tryptorelin acetate.

[Tall_Allen in reply to tonmead]

It's an important trial - thanks for participating. How do you know if you are getting the drug or the placebo?

[petercraig2]

FYI re: Metformin Use and All-Cause and Prostate Cancer–Specific

Mortality Among Men With Diabetes

ascopubs.org/doi/10.1200/JC...

My surgeon for RP was a co-author on this paper but stranger than fiction he did not prescribe this to me.

I left and went to another oncology center and a doctor who prescribed both Metformin as well as Estrogen patches for which I am eternally thankful.

[E2-Guy in reply to petercraig2]

Are you diabetic and are E2 patches the only form of ADT that you have been using since January of 2018 when your PSA dropped down to 0.17? Is your PSA still remaining at low levels?

[petercraig2 in reply to E2-Guy]

Hello,

No I am not diabetic or pre-diabetic simply from Report from Princess Margaret

Oncology team recommended Metformin as improved mortality rates from all causes.

I had RP in January 2017 and did have 35 sessions of radiation even thought I had already started Estrogen patches with significant decrease in PSA.

PSA peaked at 17 in Feb 2017 following RP with Estrogen patches has decreased over time and been <.008 since March 2019

[E2-Guy in reply to petercraig2]

Great info! Are you using the patches with only Metformin? Keep doing what you're doing, obviously!

[petercraig2 in reply to E2-Guy]

Correct, just patches and metformin as prophylactic measure as well a calcium & magnesium to keep bones strong.

[EdBar]

I take 2000 mg per day per Dr. Myers for the past 6 years. I take 1000 in the am and 1000 in the pm. No SE’s, Publix offers it free of charge with a script. My GP gave me the first script after I shared with him what I read in Snuffy’s books, soon afterward I became a patient of Snuffy’s.

None of my current MO’s have a problem with it including Dr. Sartor.

Ed