will loweing my zyprexa dose lower my sedation?

[Anon54]

zyprexa has a half life of over 24 hrs so i guess that means it builds up in ya system till it hits a ceiling or a plateau.
I take 5mg a night & im feeling tired during the day. If I lower it to 2.5 mg will it be less sedating or will it just build up in my system over time & be just as sedating as 5mg

Valium also has a half life of about a week but because ya get a tolerance to it the effect doesnt raise each day ya take it but ya dont get a tolerance to zyprexa

it's probably obvious that halving the dose of zyprexa with reduce the sedation but i just wanted to make sure

 

[ErgicMergic]

No experience with anti-psychotics, but yes, the lower the antagonism of Dopamine, the less sedation and amotivation and depression side effects from Zyprexa.

To be honest, if you are taking it for schizophrenia or Bipolar, then you might not want to raise it, you might be sedated for a reason, no offense.

 

[Anon54]

I take it pretty much for insomnia and anxiety. its prescribed off label.
i just wanna know that if i lower the dose i will feel less tired during the day. (i know its the zyprexa making me tired)

like i said the half life is zyprexa is more than a day. & i was wondering if dose really mattered as it may eventually plateau at its ceiling dose because each time u take it it builds up in ya system. it would just build up slower at a lower dose. get what i mean?

hypothetically say I cut down from 10mg to 5mg. on 10mg the amount in my system would be like this

day 1: 10
day 2: 15
day 3: 20
day 4 25
day 5 30
(because its effects last over 24 hrs so it would build up till it reaches the max it can in ya system.)

if i were to take 5mg:

day 1 5
day 2 7.5
day 3 10
day 4 12.5
etc. etc. till it ended up 30 anyway (hypothetically assuming that's the most that ya body can take)

it would take longer to build up but id have the same amount of zyprexa in my body over time no matter what dose i took. or this that wrong?

would there simply be less zyprexa in my body over a long period of time if i took half the dose?

so yeah because the zyprexa builds up in ya system would changing doses do anything or would it simple mean that a smaller amount would take more time to build up to the same level?

 

[nAON]

It doesn't work quite like that, your body reaches an equilibrium eventually, taking a lower dose WILL result in lower levels.

Lemme try to explain, if X2 is day2, X3 is day3 etc., the level in your blood on day 3, assuming half life is 24h and you're taking 5mg a day, X3 = (X2/2)+5
(today is half yesterdays levels + 5)

So the levels for 5mg would look like this:
Day1: 5mg
Day2: 7.5mg
Day3: 8.75mg
Day4: 9.38mg
Day5: 9.69mg
Day6: 9.84mg

While for 10mg would be:
Day1: 10mg
Day2: 15mg
Day3: 17.5mg
Day4: 18.75mg
Day5: 19.37mg
Day6: 19.68mg

tl;dr taking a lower dose will result in lower levels in body, so yeah, decreasing your dose will decrease your sedation in the long run

 

[Swain]

@Anon I am not sure what formula you are using to calculate your daily levels, but that is not accurate. As the days leading up to equilibrium/steady state go on, you will see the level of Zyprexa in your system is increasing less and less until you hit equalibrium and there is no longer any increase from the day before. Naon's numbers are a perfect example (if you are assuming a 24 hour half-life). Keep in mind the half-life is something like 20-50 hours which depends on factors some of which are specific to the individual. These numbers are by no means a spitting image of what will be in your body but it's a good reference point and great way to illustrate what is going on as a result of a long half-life.

These are naons numbers, which he got by assuming a 24 hr halflife .

To determine the number for the next day, you take half of the previous day and add 10 to that number. The reason you do that is after 24 hours half of the previous day's dose still remains and you are adding another 10mg in when you take your daily dose.

For example let's look at day #4 and see how he arrived there.
I am going to multiply .5 * (the previous day which is 17.5mg) then add 10mg.
So half of 17.5mg is 8.75mg, plus 10mg brings us to 18.75mg.

10mg daily would be:
Day1: 10mg
Day2: 15mg
Day3: 17.5mg
Day4: 18.75mg
Day5: 19.37mg
Day6: 19.68mg

See how small the increase was from day 5 to 6 compared to days 1-2?

If you were to chart it on paper with days on the bottom and mg's on the left the curve would look something like this one below.. eventually smoothing out to a straight line (steady state mofuggaaaa).

If half-life worked the way you were calculating it, and we looked at a drug like methadone which has no ceiling & a comparible half life to Zyprexa. What would that mean for day number 300? According to your calculations if one was taking 10mg daily on day 300 we should now have 1,505mg of methadone accumulated in your body.

NSFW:

day 1: 10
day 2: 15
day 3: 20
day 4 25
day 5 30
...
day 10 55mg
...
day 100 505mg
...
day 300 1505mg

Zyprexa does not have a ceiling does like buprenorphine does for instance. With bupe, once you hit 32mg there is no additional effects if you take more bupe. Meaning if you take an extra 16mg on top of the 32mg it will not make any difference what so ever.

If you lower your dose, you are going to lower the overall levels of zyprexa in your body. So yes, it will be less sedating. The long halflife means that it will take about 3 days to reach equilibrium as naon put it, or a steady state of zyprexa in your body at all times assuming you dose on schedule every day.

This depicts the accumulation of drugs in your system as you reach a steady state:

This depicts the 'steady-state' meaning you have the same amount of Zyprexa entering your body and exiting your body every day assuming you dose accordingly and on time.

It seems like the maximum recommended dose is 20mg daily. I just thought I would mention that.. but it has nothing to do with a ceiling dose. I can not find a shred of evidence that Zyprexa has a ceiling dose..which is not surpising. It's pretty rare for a drug to have a ceiling. The only one I know off the top of my head is bupe.. but I am sure there are more.

Equilibrium/steady state does not mean the body is saturated with as much of the drug as it can take. It means that the levels of it in your blood are now steady.. meaning if you have x amount of zyprexa in your blood at 2pm today, you will have that same amount tomorrow at 2pm, and so on, assuming there is no interruption in your dosing schedule.

 

[galfun]

Not quite...it is a little bit more complicated then this.

Lets define X as the rate of entry into your body. Define E as the rate of elimination from your body. Now for the sake of simplicity, we will assume X to be linear and E to be parabolic. Lets say n is the amount of drugs in your system at a certain point with respect to time. Basically this will define the amount of drugs in your system at a particular time as a second order PDE. Assuming t>0 still does not give enough boundary conditions. You need to be able to define both an initial condition and the amount at a particular time t>t_o. When you do, you should get something in the form of n*D(X-E)/dt=(X-E)C1+C2 and n=C2. Solving for C1 and C2 you could model the dif. eq. By the way it is a PDE because DX/dt (similarly for DE/dt) is the material derivative of the form DX/dt=∂X/∂t+determinate(gradient cross X) such that the gradient is over the differential increase in system concentrations in different areas of the body. It is a LITTLE bit more complicated then just a super simple half life expression. I could never trust the math skills of a profession where you have to stop learning math at 2 dimensional integrals. You probably need to do a fourier series expansion to determine at a particular place in the body at a particular point in time what the concentrations are. Oh, and by the way, short of placing sensors all over your body inside veins and so forth there is little that can be done to determine an accurate reading. Urinary/sweat/hair sample measurements only determine the amount eliminated. Yes it may be as simple as m dot in = m dot out...But the kinetics of the reaction are indeterminate. You COULD use superposition at different points do determine how it is elsewhere, but again that would necessitate readings all inside your body.

If you understand what I am saying feel free to give a holler if you think I am wrong.

EDIT: Oh, and its NOT steady state...this would be analogous to a turbulent flow rather than a laminar flow so you could just determine a mean quantity over a period of time.

 

[Swain]

Believe me, I am fully aware that this simple formula is not a way to accurately measure these half-life related numbers. I wrote the sentence below in my post.

These numbers are by no means a spitting image of what will be in your body but it's a good reference point and great way to illustrate what is going on as a result of a long half-life.

The point was to try and give the dude a basic understanding of what happens when your half-life is 24 hours+ and you are dosing every day. Just a general idea of how the meds pile up and what not

I didn't even think it was possible to determine the real numbers...simply because of the human body being major wild card. We are all different. But it sounds like you have a way which is pretty sweet man.

 

[Anon54]

gallfun that was the most complicated post ive ever read but i dont need to know all that.
the main thing is that if i take a lower dose of zyprexa over time it will plateau at a lower amount in my body!
so this is defenetly correct?
Remember zyprexa has a HL of over 30 hrs so those ppl baseing there info on 24 hrs might be getting incorrect results

I dont need to know the exact science i just wanna know that i'll be less tired if i take less zyprexa

obviously it would build up like in this chart.

r u experts here SURE that taking a smaller amount even over a long period will result with less in my body & wont simply platuea at the same ceiling amount?

because if it does i'll change to seroquel which only has a HL of 6 hrs