How to calculate dosages and dilutions? Spreadsheets and calculators

[Altostrata]

Here is an explanation of drug dilutions, for those who like to look at a handbook:

 

http://www.baxterhealthcare.co.uk/downloads/healthcare_professionals/therapies/pharmacy_services/ps_calc_guide.pdf

 

Also useful for converting liquid meeasurements http://www.onlineconversion.com

 

Thanks to our member Angel7366, who supplied these tips.

[Songbird]

Admin note: Also see Using a digital scale to measure doses, which explains more about the scale itself and how to measure small amounts on it.

 

03 07 18 Merged several topics about spreadsheets and calculators.

 

For spreadsheets and calculators, jump to these links:

 

Excel spreadsheet to calculate dose weights using a scale

Songbird's spreadsheet, explanation is below in this post with download links to Excel files. (You will need MS Excel or equivalent to use this.)

 

Online spreadsheet for dose taper calculations

This is a Google doc from brassmonkey -- There are different tabs at the bottom; one shows the "brassmonkey slide". Feel free to download this: Select File (in the spreadsheet, not in your browser), then download. 

 

nz11's THE WORKS spreadsheet

See .zip file for download at the bottom of the linked post.

 

Tapering calculator at ReversePsychiatry.org

This is an online calculator by DoctorMussyWasHere.

 

---

 

Calculate dose weights using a scale - Excel spreadsheet

 

Dose_weights_SA.xlsx

 

Dose_weights_SA.xls

 

If you are tapering using a scale, you will need to convert each dose to a weight so that you know what your scale should be displaying for the dose you want. The instructions are actually inside the spreadsheet but here is a little more detail:

1. Enter the dose of one whole pill in the orange cell (e.g. if your pills are 20mg pills then type in 20, or if your pills are 10mg pills then type in 10). Press tab.

2. Enter the weight of one whole pill - after calibrating your scale, making sure it is in 'gram' mode, weigh one pill and type the weight in the turqoise cell (e.g. 0.336). Press tab. (Note: some people like to weigh several pills and take an average in case the weights of the pills vary).

3. Enter the percentage drops you want to do for your taper in the green cell (e.g for 10% type in 10, for 5% type in 5). Press tab.

4. Enter the starting dose for your taper in the yellow cell. (For some people this will be the same as the dose of one whole pill above, if you are currently taking one whole pill as your dose.) Press tab.

The spreadsheet will now calculate your doses and the corresponding weights for your taper. For whichever dose you are dropping to (in the yellow), your scale should say the number in turquoise next to it. i.e. that's what you are aiming for when you cut and weigh your pills.

The spreadsheet has been protected so that you can only type in the cells you need to enter data into. This is to prevent you messing it up by accidentally typing other places! I hope this makes some sense. Any questions, just ask.

 

 

Edited December 4 by ChessieCat
moved links to top

[Altostrata]

Thanks so much, Songbird.

 

Please note you will need Microsoft Excel or some other program that can read Excel spreadsheets to use this tool.

[Songbird]

If you don't have Microsoft Office, you can download Open Office which is similar to MS Office and can open MS Office files, but it is FREE.

[Songbird]

I have included a second worksheet for those who are doing drops of so many mg rather than a percentage.  If you are doing, say, 0.5mg drops, you enter this is the green cell.  The only problem with this method is that with the same drop each time your percentage drop gets bigger and bigger, so you really need to reduce your drops as your dose gets lower.  The spreadsheet shows you what percentage each drop is so you can see when it will start to get too high.  When you want to change your drop you can create a copy of the worksheet, change the drop amount and enter your current dose as the starting dose.

[ladybug]

Hi Songbird,

 

just wanted to say thank you for providing us the spreadsheet. I downloaded both of them and I think it would be really helpful for those thinking of tapering from their ADs. I know weighing your dose is better and I'm actually planning on buying a scale but when I've checked Amazon, all the Gemini scales look the same but different prices. I don't really know which one to pick, please advice me which one is the genuine scale,  thank you.

 

Cheers,

DePrssd5

 

I've used the Gemini-20 scale for years and I believe this is the one most scale users use. I recently ordered a new one after my old one started acting up, and it didn't work and I had to return it. I'm afraid their quality is not as good as it used to be. This was my 4th scale. They seem to last about a year or two and then stop working as well. I will probably order another one and hope it was just a one time thing. It's a good deal at only 22 US dollars and gets the job done.

[DePrssd5]

Hi LB,

 

Thanks for the quick response, so what does it actually show or do when you said it wasn't working. Just in case it doesn't measure the weights accurately. But you are right, the price is quite affordable but I need to pay more coz I live in Australia. But it's ok as long as it does iit's job. Thanks you once again LB, good luck on the taper.

[ladybug]

Hi LB,

 

Thanks for the quick response, so what does it actually show or do when you said it wasn't working. Just in case it doesn't measure the weights accurately. But you are right, the price is quite affordable but I need to pay more coz I live in Australia. But it's ok as long as it does iit's job. Thanks you once again LB, good luck on the taper.

 

When it's stops working as well, the weight readings bounce around frequently. I weigh the pill pieces with the calibration weight on the pan as this puts it in the middle of the weighing range which is supposed to help with accuracy. The calibration weights are usually 10g so I try to get it to read as close to 10g as possible. I will usually accept +/- .002g and then adjust my pill weights accordingly. But, when it starts reading much more than that, say 10.010g and frequent calibrations, new batteries, etc. don't help then I give up and order a new one. My very stability depends upon this scale so I need it to be accurate as possible. I hope this helps. And if you have any questions when you receive the scale, I'll be happy to help you!

[Jlynn]

Is there a spreadsheet for tapering 10% using the liquid Paxil? I know there used to be one on PP and I can't find one online anywhere! If I was smarter with Excel I would create one but I am not  

[Songbird]

I don't think you would need a special spreadsheet for that.  How many mg per ml is your liquid?  You could probably use the weight column as a ml column.

[Jlynn]

It is 10 mg / 5 ml for the paxil liquid. So if I were to taper to say 16.2 mg how many ml would that be? I am so bad at math and my brain is swiss cheese at the moment!

[Songbird]

It is 10 mg / 5 ml for the paxil liquid. So if I were to taper to say 16.2 mg how many ml would that be? I am so bad at math and my brain is swiss cheese at the moment!

 

You can use the weight column as a ml column.  So enter 10 in the gold cell, then enter 5 in the turquoise cell.  Are you currently taking 20mg?  So you would enter 20mg in the yellow column. 

 

Using the percentage drop from the green cell (e.g. 10%), your dose drops will be shown in the pale yellow cells.  You can then use your syringe to measure out the doses shown in the pale turquoise cells.

 

Try this and you'll see that to get a dose of 16.2mg you'll need 8.1ml liquid.

[pattypurple]

Hi there. New to all of this. I'm embarrassed to say I have difficulty with math (due to ECT and hey, maybe also due to all these meds(?!)). Can someone tell me what is 10% of 5mg? Is that .5mg? Do you multiply by .10 and then subtract that from the total dose? 

 

Thank you for not laughing or screaming or sighing (or at least keeping it to yourself!)

[bows head in shame]

 

Edited March 8 by Altostrata
merged related topics

[dalsaan]

Hi there. New to all of this. I'm embarrassed to say I have difficulty with math (due to ECT and hey, maybe also due to all these meds(?!)). Can someone tell me what is 10% of 5mg? Is that .5mg? Do you multiply by .10 and then subtract that from the total dose? 

Thank you for not laughing or screaming or sighing (or at least keeping it to yourself!)

[bows head in shame]

 

No need to bow your head in shame - that is the way to calculate your dose reductions.  Dose X .10 = amount to be deducted from current dose

[bluebalu86]

Hi patty

 

This is what I could do. I will have my father help out with this when he comes home he's really good with math. I calculated these with an Excel spreadsheet. This is the dose minus 10% of the dose, starting from 5 mg. If you are using an Excel spreadsheet you should create two separate columns A and B. A is where you write the current dose, and for B you use the formula B1=(A1-(A1*10%)). Then you copy the formula all across the column and it calculates each new dose.

 

These are the numbers I came up with. May or may not be correct. 

 

5.00 4.50 4.05 3.65 3.29 2.96 2.66 2.39 2.15 1.94 1.75 1.58 1.42 1.28 1.15 1.04 0.94 0.85 0.77 0.69 0.62 0.56 0.50 0.45 0.41 0.37 0.33 0.30 0.27 0.24 0.22 0.20 0.18 0.16 0.14 0.13 0.12 0.11 0.10 0.09 0.08 0.07 0.06

[bluebalu86]

You're most welcome. Make sure you double check everything. If X is the old dose and Y is the new dose, you do the math like this:

 

Y = X-(0.1 x X)

[Skyler]

I just came across a math tool that will calculate the % of however many mgs. you want to cut.  Use the first box, and enter % you want to reduce in the first space, and the number of mgs. you are taking in the second, then hit calculate.  Just do the same with each successive dose, and it will give you the figures you need for your taper.

[BuddhaMama]

I understand how to calculate 5% of my original dose (15mg - .75mg=14.25mg), but what I don't understand is how to translate this to my 1ml syringe. If my suspension liquid contains 15mg per 1ml, how do I calculate 14.25mg in a 1ml syringe?

[nz11]

okay after doing a search i found that remeron can be bought in 15mg per ml solution.

 

I was just surprised that you can dissolve 15 mg in just 1 ml but apparently you can.

 

okay in that case if you want 14.25 mg you need to take 0.95 ml.

 

You simply divide the desired mg dose by 15 and take that in mls.

 

nz11

note to myself:  2 dp is needed in my liquid spreadsheet calculator not one.

[ChessieCat]

 

Hi there. New to all of this. I'm embarrassed to say I have difficulty with math (due to ECT and hey, maybe also due to all these meds(?!)). Can someone tell me what is 10% of 5mg? Is that .5mg? Do you multiply by .10 and then subtract that from the total dose? 

Thank you for not laughing or screaming or sighing (or at least keeping it to yourself!)

[bows head in shame]

 

No need to bow your head in shame - that is the way to calculate your dose reductions.  Dose X .10 = amount to be deducted from current dose

 

 

I find it easier to just multiply the dose by 0.90 for a 10% decrease or 0.95 for a 5% decrease.

 

Or you can use the above way and then double check by multiplying by my suggested method.

 

Explanation:  0.90 = 90% and 0.95 = 95% so you are calculating the amount of dose you need, not what you need to deduct.  Doing it this way means one less calculation therefore reducing the risk of error.

[Madeleine]

Somebody posted a spreadsheet on the site that is a dose calculator.  Does anyone know where I can find it. I saw it but now don't know where it was.

Many thanks!

 

M.

 

Edited March 7 by Altostrata
deleted Mod Note

[ChessieCat]

Here's what I have found:

 

Excel spreadsheet to calculate dose weights using a scale

 

Online spreadsheet for dose taper calculations

This is a Google doc -- There are different tabs at the bottom. Feel free to download this: Select File (in the spreadsheet not in your browser), then download. 

 

nz11's THE WORKS spreadsheet

Edited March 8 by Altostrata
updated links & added additional information

[Madeleine]

Thank you!

[BuddhaMama]

okay after doing a search i found that remeron can be bought in 15mg per ml solution.

 

I was just surprised that you can dissolve 15 mg in just 1 ml but apparently you can.

 

okay in that case if you want 14.25 mg you need to take 0.95 ml.

 

You simply divide the desired mg dose by 15 and take that in mls.

 

nz11

note to myself:  2 dp is needed in my liquid spreadsheet calculator not one.

 

I think the reason I'm having such a hard time with the syringe is because I want to do the BrassMonkey slide method of 2.5% decreases. My 1ml syringe only has 5 tick marks between each 10th of a ml. So, my first decrease of 2.5% would fall somewhere between the tick marks that lie between 1ml and .9ml, which makes me feel like it's a lot less accurate and therefore more likely to throw my body off. I'm super duper sensitive. Should I use a digital scale? all the searching I've done on SA regarding scale usage seems to only discuss tablets, powders and beads, not liquids. Help please!

[LexAnger]

You can dilute the liquid 10 times by adding water into it, then the measure should be much more accurate.

[ChessieCat]

Have you seen this topic:  Using an oral syringe and other tapering techniques

[Faye]

Thank you for posting this advice I've found it extremely helpful. X

[ChessieCat]

I've just posted this to help one of the members so I thought I'd post it here for others:

 

 

An easy way to work out your next taper dose (a 10% reduction) is to multiply the current dose by 0.9 (if making a 5% reduction multiply by 0.95).  This will be the dose you need to take.  If you want to double check your calculations you can also multiply the dose by 0.1 (for a 5% reduction multiply by 0.05) and then deduct that from the previous dose.

 

Current dose = 20mg

 

1st reduction:     20mg x 0.9 = 18mg       double check:     20mg x 0.1 = 2mg   so   20mg - 2mg = 18mg

 

2nd reduction:    18mg x 0.9 = 16.2mg   (if you can't easily measure 16.2mg round up to 16.25mg or 16.5mg - NOTE always round up)

 

 

Please note that the next reduction needs to be calculated on the dose you took:

 

3rd reduction (choose one of these doses):

 

16.2mg x 0.9 = 14.58mg         (eg round up to 14.6mg or 14.75mg)

 

16.25mg x 0.9 = 14.625mg    (eg round up to 14.75mg)

 

16.5mg x 0.9 = 14.85mg         (eg round up to 15mg)

 

 

Remember that the next reduction needs to be calculated on the dose you took on your 3rd reduction.

 

Edited February 28 by ChessieCat

[Centime]

I have a mg. scale, and know how much one 10 mg. Paxil tablet weighs. I can easily figure how to cut it by 10%, then 10% of that dose, and so forth. But the site asks that we report our tapering progress in mg.s. How do I covert pill weight back  to mg.s?  I’m bad at math. Can anyone help me with this? Thank you!

[brassmonkey]

You would use the same calculation as you used for the dose weight. For a 10% reduction:

10mgai X .9 = 9mgai

9mgai X .9 = 8.1mgai

 

For the weight of the actual dose, from the scale, we like to use the sufix mgpw, milligrams pill weight (i.e. 125mgpw)

For the strength of the dose we like to use the sufix mgai, milligrams active ingredient (i.e. 9mgai)

 

This makes it a bit easier to follow which measurement is being talked about.

 

Hope that helps.

[Altostrata]

Merged post about calculating dilutions.

[Surfchick]

Here is the calculator we built-  this micro-dose calculator includes the 2 week hold per Brassmonkey's slide recommendations...

 

www.taperoff.co

[brassmonkey]

Hi Surfchick-- The calculator looks good and my first quick test was fine with one exception.  The year column only indicated which page you were on and not the time spent to that point.  My test of  40mg at 10% showed a taper length of 2 years when it should have been more like five to five and a half years. This could be very misleading for people trying to make plans.

 

Brassmonkey

[Surfchick]

Ok i see it only goes down to .09mg.. 

Feel free to delete the post, im not sure why its stopping at .09

[brassmonkey]

My mistake, I entered the percent of taper wrong. Never mind.  It is showing that the taper will take seven plus years to complete, which mathematically is correct, but in practical terms not doable.  The physical limitations of making the reduction below 1mg make it very hard to complete the taper in this manner. It may be an idea to add a note about this and truncate the program at some point.  I'll take more of a look at it.  There is some discussion on this problem on the Brassmonkey Slide Method of micro tapering thread.

 

BTW I do like the calculator and think it will be very helpful.

[Surfchick]

OK ill talk to my husband, he built it for me, and to share. This is just the first draft  He's working on an app as well for itunes this next year. 

It is a great way to get started!