razzlesf, I can see how figuring out 10% of 120mg Cymbalta -- an extraordinarily high dose -- would be very confusing via the bead-counting method!
We recommend reducing by 10% per month, calculated on the last dosage. This seems to be safe for most. It could be too safe for some, who conceivably might be comfortable tapering faster. Your nervous system will determine the length of time it takes.
Doctors tell people to taper by, say, 20mg or 30mg because they don't have the faintest idea what a gradual taper might mean, they don't recognize withdrawal symptoms, and they cannot conceive of a dosage different from that provided from the manufacturer in the pharmacy-vended capsules.
I definitely would NOT count on being able to reduce faster or by a greater percentage as you go lower in dosage. People tend to have the greatest difficulty in the last leg of the taper (see Why taper? Paper demonstrates importance of gradual change in plasma concentration )
We can't tell in advance who can taper more rapidly, so we recommend starting at the most conservative rate. The only way you can find your own personal rate of taper is by trying it. The way to speed it up is to make 10% (or less) decreases at shorter intervals, not to make bigger decreases. I would not go faster than a decrease every 2 weeks, to see if withdrawal symptoms occur. (If you end up with extra capsules of any strength, save them in a container marked with the original dosage.)
This is how I'd do a 10% decrease in your situation, in the easiest way possible.
1st decrease 120mg --> 110mg
As you have observed, you are taking 120mg now, you can get your prescription filled with 60mg + 30mg + 20mg capsules to take a total of 110mg. That could be your first 10% decrease.
You can see how you tolerate that. If it all goes smoothly, you may wish to make your next 10% decrease in 3 weeks rather than 4 weeks.
2nd decrease 110mg --> 100mg
For the second 10% (or less) decrease, if I were you, I'd go to 100mg. I'd have my prescription filled with 60mg + 30mg + 20mg capsules (totaling 110mg) and take only half of the 20mg capsule, for a dosage of 100mg.
You can calculate half a 20mg capsule by weight. If that is impossible, if I were you, I'd get a compounding pharmacy to make 10mg capsules. You will need a prescription for this. (At the end of this period, you will end up with 30 extra 10mg capsules. Save them in a separate container marked with the current dosage, 10mg, and the original dosage, 20mg.)
3rd decrease 100mg --> 90mg
Get your prescription filled with 60mg + 30mg capsules for a total dosage of 90mg.
4th decrease 90mg --> 80mg
This is slightly greater than 10%, but if you've been doing well so far, it should work.
Get your prescription filled with 60mg + 20mg capsules for a total dosage of 80mg.
This brings you down to 80mg with the least amount of manipulating the capsules.
5th decrease 80mg --> 75mg or 72mg
Going to 75mg would be a decrease of 6.25%, but does not require a lot of capsule fiddling. To taper by 10%, to 72mg, you'd either have to count beads or have custom capsules compounded.
I would get my prescription filled with 60mg + 30mg capsules. Take only half of the 30mg capsule, calculated by weight, for a total dosage of 75mg. (At the end of this period, you will end up with 30 extra 15mg capsules. Save them in a container marked with the current dosage, 15mg, and the original dosage, 30mg.)
If you choose to get custom compounded capsules, you might as well get your prescription filled with 60mg capsules plus 12mg custom capsules, for a total daily dosage of 72mg.
6th decrease 75mg --> 67.5mg or 72mg --> 65mg
If you're taking 72mg, get the prescription filled with 30mg + 20mg capsules. Add the 30 extra 15mg capsules from the prior decrease for a total daily dosage of 65mg.
If you're taking 75mg, get the prescription filled with 60mg capsules. Add 7.5mg by weight or by bead-counting from your extra capsules for a total daily dosage of 67.5mg.
If you choose to get custom compounded capsules, you might as well get your prescription filled with whatever calculates out to be a 10% reduction on 75mg or 72mg -- 67.5mg or 65mg custom capsules.
7th decrease 67.5mg or 65mg --> 60mg
Get your prescription filled with 60mg capsules.
8th decrease 60mg --> 55mg
Get the prescription filled with 30mg + 20mg capsules. Add either half of the 10mg capsules you have saved, or get 5mg capsules compounded for a total daily dosage of 55mg. (At the end of this period, you will end up with 30 extra 5mg capsules. Save them in a container marked with the current dosage, 5mg, and the original dosage, 30mg.)
9th decrease 55mg --> 50mg
Get the prescription filled with 30mg + 20mg capsules.
10th decrease 50mg --> 45mg
Get the prescription filled with 2 20mg capsules. Add the 5mg capsules you have saved for a total daily dosage of 45mg.
11th decrease 45mg --> 40mg
Get the prescription filled with 2 20mg capsules.
After this, you're going to have to either open up 20mg capsules and count beads, or get custom compounded dosages.
If you decide to count beads, to decrease your dosage you could remove a set number, 10 beads for instance, per month or whatever interval you choose for your taper. (Put the beads you remove in a container marked with their original dosage.) You'll get a very good idea how often you can decrease by 10 beads. It might be monthly, every 3 weeks, or 2 weeks.
Depending on your reactions to decreases of 10 beads, you may wish to make smaller decreases when you get down to the last 20mg capsule. Do not be surprised if you have to slow down or even decrease bead by bead at the end.