Missing a day of Zytiga

[Huzzah1]

Is it a big deal to miss a day of Zytiga+Pred?

I’m having a knee replacement on Monday and I’m not supposed to have any food in the AM.

[Derf4223]

Zytiga is supposed to be taken without food.

[Huzzah1 in reply to Derf4223]

Correct, but Prednisone with food.

[dhccpa in reply to Derf4223]

Many do the 1/4 dose with food. To each his own.

[Still_in_shock]

1 day with no Zytiga and Prednisone is OK.

I missed one for a PET scan, nothing changed.

[GoBucks]

No big deal. I stopped for 7 weeks once.

[Pinkyboy]

When I was transitioning from Abiraterone to Nebeqa, I 'missed' a few days. My MO said nothing at all to worry about.

The thing for you to worry about is the posibility of pulmonary embolism. I had one 21 days after my TKR surgery in 2022 and it very nearly punched my ticket. They sucked blood clots out of my lungs for an hour and 47 minutes. And I followed all of the pre and post-op instructions.

[Huzzah1 in reply to Pinkyboy]

In retrospect, what could you have done to prevent that from happening? I will be on blood thinners, wear compression stockings, in home PT and RomTech device. I am told to never stay still for longer than 1 hour.

[Pinkyboy in reply to Huzzah1]

I really don’t know what I could have done to have prevented the PE. I faithfully used the SCDs (sequential compression devices) on my legs both on the hospital and at home. I was not instructed to wear compression stockings, so maybe that is something I should have done. I know, there are countless TKR procedures done and comparatively few PEs, so I was just unlucky I suppose. I think your plan of never being still for more than an hour is an excellent thing.

I sincerely wish you all the best for an ‘event free’ procedure and a quick recovery and return to better-than-normal.

Robert

[Huzzah1 in reply to Pinkyboy]

I am also having the Quad Sparing method which results in much less tissue damage. I'm hoping for the best!

[JohnInTheMiddle]

Lots of people have a casual approach to saying it doesn't matter to miss a dose of Zytiga or Abiraterone. And you'll never know - least right away. Eventually though most of us will run into resistance. Who knows why resistance develops? Is it little steps along the way where we miss something there or whatever? The fact is that the half-life of Abiraterone is not that long.

If you miss a dose you won't notice anything - but you'll probably have a little spike in testosterone and your cancer might notice. And then you go back on the ARPI and everything's fine. But who knows over time if we do it once every little while?

And so take the Zytiga as per usual and take the prednisone with a little bit of cheese or something. And if you're really worried ask your doctor why you need to be fasting in the morning. Explain the situation.

Also I just found a website from Columbia University that says to take prednisone on an empty stomach! My perspective I'd rather not miss my ARPI dose - and maybe put up with a little stomach upset. I'm not big on the casual approach 😃

[Sailing-Todd in reply to JohnInTheMiddle]

If there is a general anaesthetic involved you need to be nil by mouth otherwise there is a risk of choking to death on vomiting.

[JohnInTheMiddle in reply to Sailing-Todd]

Thanks! You'd think that the doctors would advise and not leave it up to the patient to figure out ...

[dhccpa in reply to JohnInTheMiddle]

How long have you been on Zytiga now? Or are you still?

[Mike1971]

I had to skip zytiga and pred for a day or two because of an operation as well, and my doctor said it was not a problem.

[JWPMP]

Our experience...no expertise here. Jim had HDR BT Oct 2021 at UCSF. He spent three nights instead of one. He missed his Abiraterone/Prednisone for two days and had only been on it 9 months. I was panicked. They did not provide it at the hospital. I offered to bring it from home, they said no need. His RT Dr Mohamad, said it would be okay. As of Dec 2023, he is still >0.02. Just fwiw.

Thank you

[dac500]

If you miss Zytiga for a few day, it doesn't matter. If you have been taking it for a while, there would enough Zytiga in your system. When I took a break from Lupron, I noticed that my testosterone remained below 20 for about six months.

I have been taking Zytiga since November 10, 2023 and I missed a day because I had to go for angiogram. I asked my MO and he said no problem.

[JohnInTheMiddle in reply to dac500]

How do you know it doesn't matter DAC? Do you have any references? Your personal experience is kind of irrelevant. Have you read up on the half-life of Zytiga?

[dac500 in reply to JohnInTheMiddle]

I talked to my MO.

[Hidden]

Not a single issue missing a day or two. It's a no-stress move.

[CRPCMan]

If only that really matter. It doesn't. Trust me on this one.

[jfoesq]

I am Also having surgery soon (hip replacement) and was advised by my M.O. to go off my Zytiga 5 days before my surgery ( despite not doing this when I had a knee replacement and a disectomy several years ago. I ran this by Tall_Allen who I think said it has something do with the liver being able to process the anesthesia. So- I plan to go without it for 5 days beforehand.

[GrantB47]

I take my abiraterone (500mg - all I can tolerate) every morning and the prednisone a couple of hours later with a late breakfast.. My MO says it is not necessary to take them together. (Also on Eligard quarterly shots.) My Psa and T are both very low.

[Iloveyoudad in reply to GrantB47]

Yes, my dad also doesn't take Pred right after Abi. He takes it a few hours later or within the day with food.

[Lettuce231]

Interesting, I had a knee replacement in October, I was advised that I could continue to take Zytiga and Prednisone.

Incidentally, I take Zytiga with food and the Prednisone with a cup of tea, when I get up.

I hope your operation goes well, 🦿

[Johnkelsey]

I learned the hard way not to skip prednisone for more than a day. When I had Covid in 2022 I didn't want to eat anything and so skipped several days of meds. Ended up in the hospital not with covid issues but with adrenal insufficiency, which translates to a lack of cortisol in the body. With no cortisol, you die (Adkins disease). With insufficient cortisol you get sick fast. I learned that long-term Zytiga can cause adrenal insufficiency, which will require the addtion of an endocrinologist to your bulging portfolio of doctors.

BTW hydrocortisone is easier on the stomach than pred and easier to manage, medically they are interchangeable except the dosage is different - 5mg pred equals 20mg hydro. Both have a half-life around 6 hours, which is why we take it 2x a day, and with adrenal insufficiency, I take extra if I am ill or under stress - cortisol is the flight-or-fight hormone, stress uses it up fast.

[Tommyj2 in reply to Johnkelsey]

I’d be more concerned about missing the prednisone than the Zytiga…would be a lot more “comforting” if there were general consensus on the potential effects of missing doses.

“To each his own” does not begin to cover it🫣

[Apisdorsata]

abiraterone has a fairly long half life, about 12-15 hours so missing a day is not too serious. Prednisone half life is much shorter so it might be important. Your MO should advise you. And the anesthesiologist should know if the abiraterone will interact with the meds he uses.

I don't see why you couldn't just take both meds as soon after surgery as they'll let you eat, probably just a couple of hours after knee surgery.

[TuffNuttoCrack]

At my oncologist first meeting, she said that she would rather hear that I miss a week of taking Zytiga than missing a week of bulking up. We put that to the test as I spent four days in the hospital several months later trying to clear myself of pneumonia, I asked about taking it they said it was a lower priority than “saving my life, my interpretation ”. I went back into the hospital two days later with a suspected stroke and the observation unit is not allowed to give cancer drugs. I think I went without a total of 6 days in 8 days with no exercise so I was extremely week Due to the pneumonia brought on by my 1st chemo, they stopped it and I currently am on Lupron and Zytiga.

Two months later, the extremely aggressive rate cancer tumors was reduced by 2/3 according to the CT scan. In total my treatment had spanned 3 months and they were able to take the stint away from my crushed ureter and restore my kidney function. Each person is different but in my opinion I don’t think you should worry too much not for a single day.

[Biru49]

Zytiga can be taken with food if you eat a low-fat meal with it. A benefit is you only take one pill per day vs. 4 pills per day if you don't pair the single pill with food. I eat a low-fat breakfast every day and take one Zytiga pill, one Prednisone pill and an Orgovyx pill at the same time. I save over $200/month by not having to buy the other three Zytiga pills per day. Check with your doc about the details of what constitutes a low-fat meal for this purpose.

[SteveTheJ]

Erleada and Lupron are both long-acting. I had a situation last year where I lost a month's worth of Erleada and my oncologist told me not to worry about it. The lapse was in fact about 2 weeks IIRC. Hope that helps.

[SeosamhM]

This is likely...definitely... way more than anyone is looking for, but...

The "half-life" of a medication only matters in terms of building up to a therapeutic dose of the medication that is in a "steady state" in our bloodstream if the dosing amount and timing is correct. Imagine trying to keep a balloon up in the air above your head by blowing - you could use many small puffs of air (smaller "doses") to keep it above your head (the "therapeutic dose"), or you could use a massive blow (big dose!) to get it up high and then wait longer to give it another go before "dosing" the system with air. Obviously, by using many smaller puffs of air, you theoretically have greater control of the system. The question is whether missing a dose of air effectively crashes the therapeutic dose.

It could. See the first reference below. The established therapeutic dose for abiraterone is 8.4 ng/mL of plasma. Apparently - and I just learned this - only "...65% of patients treated with a fixed dose of AA (1000 mg once daily [without food]) reach the target concentration of 8.4 ng/mL." (Yes, it is likely that 35% of us are not getting the target dose, and should be taking abiraterone with food to increase its bioavailability!)

In statistical terms, 8.4 ng/mL is a very low concentration with respect to the original pharmacokinetic (PK) study for abiraterone, which resulted in the lowest (average) plasma concentration of about 50 ng/mL (see second reference). If you meet this average, then missing a few days won't affect the therapeutic dose. But if have a low plasma concentration of abiraterone, you aren't doing yourself any favors.

The first reference paper is eye-opening and disappointing. It concludes that monitoring for plasma levels of abiraterone is not cost effective - even in the face of up to 35% of men not getting the full effect of abiraterone as they should.

sciencedirect.com/science/a...

accessdata.fda.gov/drugsatf...

[BigCDrugSurfin]

Your MO should confirm. I had a procedure and did not take it the day of.

[Mozart123]

When my husband had knee replacement, we were requested to bring the bottle of xtandi to the hospital since that isn’t a med they stock. They gave him the meds later and he never missed any doses.

[lokibear0803]

First, apologies for a long-winded post. I thought it was an interesting question, and pulled together some various pieces I’ve had for a while + did some extra digging. Anyone with biochemistry expertise is invited to elaborate and/or correct me where I’m off-base:

From recent discussions with my MO:

T levels of 50-200 are a “sweet spot” for PCa.

From my own reasoning:

If the ABI is lowering your T to undetectable, it would be impressive if your T level recovers that quickly so that the tumors “notice” (i.e. up to 50 or more within one day). I think most of us would be ecstatic if our T recovered that quickly during ADT vacations (for those that do this). I’m guessing that most of us here don’t use “ecstatic” to describe our day-to-day.

Even if any tumors did “notice”, it would likewise be impressive if the bounce they get from say 24 hrs of elevated T had any noticeable effect on any long-term outcome. The next day’s ABI dose would “soon” remove the fuel, and any tumor that “noticed” would return to a suppressed state.

FTM depending on how long you’ve been taking ABI, some percentage (hopefully a large percentage) of your tumors become dormant, and again it would be impressive if they woke up quickly enough to respond. Or, perhaps, I’m misreading the meaning of “dormant”.

So any non-dormant tumors with the ability to notice a small bump in T (that seems unlikely to occur anyway) might respond with a small amount of growth, but again it would be impressive if these tumors had enough time to mutate towards, e.g., castrate resistance or neuroendocrine. Speaking strictly for me — it’s the mutations towards more aggressive cancer that worry me, not some tiny amount of tumor growth.

Regardless, we have this:

…from various scientific resources/articles:

The production of T is done thru two multi-step pathway starting from cholesterol, or a 3-step pathway starting from DHEA-S. Starting with cholesterol, depending on which path is taken, there are 4 or 5 steps needed to get to T production. Abiraterone inhibits CYP17A1, which is needed for steps 2 and 3 of the 4-step pathway, or steps 3 and 4 of the 5-step pathway. ABI “permanently disables” CYP17A1 rather than “competitively inhibits” its (as e.g is done using ketaconazole).

I will admit ignorance of the biological implications here, but I’m not inclined to interpret “permanent” literally. From various articles, it appears this just means it’s more difficult and less time-efficient to reverse the inhibition. So, again, it would be impressive if missing one day of ABI would make any difference.

In terms of the 3-step pathway from DHEA-S, it appears that ABI has no effect. I’m still regretful that I was taking a DHEA supplement for many months immediately preceding the first initial spike in my PSA. This sadly led to a positive biopsy. Hence my reluctance to use the word “ecstatic” discussion my day-to-day.

Finally, and I quote from drugs.com regarding missed doses of prednisone:

“Zytiga blocks the production of cortisol from your adrenal glands. Prednisone helps to replace the lost cortisol that can cause side effects such as low blood potassium levels, fluid build up (edema), high blood pressure or irregular heartbeats.“

Production of cortisol uses one of two possible 5-step pathways from cholesterol. ABI blocks steps 2 and 3 in each of these, and the missed prednisone is a double-whammy on your cortisol levels. But I would have doubts that missing one day after a long-term protocol would make a measurable difference (in potassium, etc).

However, cold turkey of prednisone for some extended time after a longer-term protocol is risky. Tapering is needed, depending on how much prednisone, and for how long, you’ve been taking it.

[dmt1121]

My MO has told me it isn't an issue because Zytiga stays in your body for 6 months.

[ImaSurvivor1]

I have a minor outpatient procedure with general anesthesia coming up. My medical oncologist who prescribed my ADT (currently Yonsa and methylprednisolone) said to stop the meds 5 days before until 2 days after the general anesthesia. I'm not sure why, but I'd read that somewhere, and the MO confirmed it for me.

[Jeremiad53]

Just slowly move up the taking of the Zytiga in time. I got tired of taking it in the AM so I start sliding it until 11 AM, In a couple of days I took it at 8 pm, and continued on. I can't get my MO to allow me to cut back. I am taking 1,000MG a day