What does an Ashton Manual calculator actually compute?
Arithmetic, and only arithmetic. Whether it is called an Ashton calculator or a benzo taper calculator, it takes the benzo, or benzodiazepine, you take now and your total daily dose, converts that dose to its diazepam equivalent using the table Professor C. Heather Ashton published in her manual, and drafts a crossover to diazepam in stages, followed by a series of reductions.
The conversion table is the heart of it. On Professor Ashton’s table, Xanax, or alprazolam, 0.5 mg is about the same strength as Valium, or diazepam, 10 mg. And, Klonopin, or clonazepam, 0.5 mg sits on the same line, as does Ativan, or lorazepam, 1 mg, which is why an Ativan taper calculator and a Xanax taper calculator are the same arithmetic.
So, three Xanax 1 mg tablets a day add up to roughly Valium 60 mg a day. A taper down from Valium 60 mg is a long road, and that is why the printout runs as long as it does.
While the calculator knows your dose, it knows nothing else about you. It does not know how long you have taken the drug, whether you have tried to stop before, or what happened when you did. So, what is a doctor supposed to do with a number like that?
Is the schedule it prints a taper plan?
No. It is a starting map.
The Ashton Manual calculator on ashtonmanual.org is a fair example. Once the crossover stages are drafted, it cuts the diazepam dose a few milligrams at a time when the dose is high and a fraction of a milligram when the dose is low, with a hold of a week or two penciled in at every stage. Those are fixed milligram steps decided by a formula, not by how you feel on the morning of the cut.
While the arithmetic is honest, it is also blind. A stage that reads well on a screen may be an easy week for one patient and a terrible one for another, and the formula cannot tell the two apart. Professor Ashton wrote her own schedules as examples to be adapted, never as timetables.
A calculator is not the only thing that reduces a taper to arithmetic. Unfortunately, the detox and rehab industry does it with a calendar: insurance covers fourteen days, so the nervous system is given fourteen days.
The person typing a dose into a calculator at midnight is almost never addicted to the drug. They are a patient whose prescription did what benzodiazepines do with long use, which is to produce physical dependence. Physical dependence is not addiction. It is a medical condition that calls for a gradual taper, not addiction programming.
What does Dr. Leeds do with the printout at the first visit?
He reads it, and then he mostly sets it aside. Patients often arrive at the first telemedicine visit with a schedule already printed, the stages highlighted and a start date circled. Mark Leeds, D.O. treats that printout as the beginning of a conversation, not the end of one.
The first question is not how fast to go. It is whether a diazepam crossover is the right move at all, and the calculator assumed the answer before you typed the first digit. In his experience, patients who can taper on diazepam have a more comfortable taper and heal faster, which is why he prefers the Ashton crossover to tapering on the original drug.
The second question is what happened before. Have you cut the dose before, and what did the week after feel like? Did a doctor ever tell you to just stop, and then send you home? What happened in the days after that? Do not leave that part out. Those answers change the plan more than any number on the page.
Of course, many patients trust the calculator more than they trust the next doctor, and they have earned that suspicion, because the prescription that caused the dependence came from a doctor. Yet, the printout gives patient and doctor a shared picture of the road, in milligrams. What it cannot show is how the next stage will feel.
When does he not cross over to diazepam?
When the patient cannot take it. Some people metabolize diazepam unusually fast or unusually slowly, and some have had an allergic or otherwise bad reaction to it or to a related benzodiazepine. In those cases, the taper runs on the medication the patient already takes.
There is no blood test that settles this in advance, and there is no shame in not knowing the answer before the first substitution is tried. The decision comes from history, from what happened on any earlier attempt, and from how the first small substitution is tolerated. A calculator cannot ask any of those questions, so it cannot make the decision.
Xanax is the special case. If diazepam is out, the preferred alternative for a patient on alprazolam is a crossover to clonazepam, or Klonopin, and a taper from there. While clonazepam is also a potent drug, it lasts much longer in the body than alprazolam, and on Professor Ashton’s table Xanax 0.5 mg and Klonopin 0.5 mg are listed as equal, each at about Valium 10 mg.
That answers the question behind a search for a Xanax to Klonopin calculator. The conversion is one line on Professor Ashton’s table. The decision to use it is not arithmetic. It is medicine.
Why is Xanax the hardest benzodiazepine to run through a calculator?
Because of the tablets. Alprazolam is potent, so the doses are small, and the tablets come in 0.25 mg, 0.5 mg, 1 mg, and 2 mg. Once you are down to Xanax 0.5 mg a day, a whole 0.25 mg tablet is half of your dose, and even a split tablet is a quarter of it.
Alprazolam is also short-acting, so the drug wears off between doses and the symptoms arrive on a clock, a pattern known as interdose withdrawal. Xanax 0.5 mg carries the weight of Valium 10 mg, but it leaves the body far faster. Dr. Leeds wrote about this at length in why a Xanax taper is the most difficult kind of benzodiazepine taper, and none of it has changed.
Unfortunately, a calculator answers the tablet problem the only way arithmetic can, with a bigger percentage jump at the end. The honest answer is different. Below about Xanax 0.5 mg, the choices are a compounded liquid, which can be measured in fractions of a milligram, or a crossover to a longer-acting benzodiazepine that comes in smaller pieces, and never a bigger jump.
Professor Ashton said as much decades ago. On September 23rd, 2020, the US Food and Drug Administration caught up, updating the boxed warning on every benzodiazepine to say that stopping suddenly or reducing the dose too fast can set off life-threatening withdrawal reactions.
Whatever the calculator prints, do not stop a benzodiazepine suddenly. Quitting cold turkey can trigger seizures and can be deadly. So, every change, from the manual’s schedules to any plan a doctor writes, should be gradual and worked out with your prescriber.
Where does the calculator’s arithmetic stop?
At the bottom of the dose, and sooner than most people expect. A fixed milligram cut is a small share of a large dose and a large share of a small one. A 2 mg cut is 5 percent of Valium 40 mg and 25 percent of Valium 8 mg, and a 0.5 mg cut from Valium 1 mg is a 50 percent cut.
The brain notices the percentage, not the milligrams. The Maudsley Deprescribing Guidelines describe why: the relationship between the dose and the share of receptors it occupies is not a straight line, so at low doses each remaining milligram does far more work than the same milligram did at the top. This is the idea behind hyperbolic tapering, where the cuts shrink as the dose falls.
An analogy that might help is the difference between a map and the weather. The calculator draws the map, with every stage marked in milligrams, and the map is accurate. What no map can tell you is that it will be raining at stage nine.
While this is not a perfect analogy, the weather is how you feel on the morning of each cut, and only you and your doctor can see it.
The calculator is not wrong at that point. It is simply finished.
Why do the last milligrams need a different tool?
Because the tablet can no longer be cut small enough, and the calendar can no longer be trusted. This is where the fixed milligram steps get left behind for a compounded liquid, with reductions of a fraction of a milligram, known as a micro taper, and a hold after each one until the symptoms settle.
A worse week after a cut is not failure. It is the nervous system reporting that the cut was too big or too soon, and the right response is to hold at the current dose, not to push through and not to jump back to the top. Patients often describe relief at hearing that a hold is allowed.
The taper should be, to a large extent, patient directed. If the pace is too fast, it is your doctor’s job to slow it down. Or, if the pace feels too slow, you and your doctor may agree to pick it up a bit, as tolerated.
Will the last milligrams be the hardest? For some patients, yes, and after months of small cuts it can feel as if the end will never come. Fortunately, the low-dose tail is also where a liquid and weekly visits do the most good, and the brain does heal, given time and a slow enough descent.
What is the next step if you already have a printout?
Bring it. In Dr. Leeds’ telemedicine tapering practice, the first visit is where the printout meets the history, and the plan is built together, with weekly appointments so the pace can change as soon as the symptoms say it should. A compounded liquid takes over when the tablets run out of room, and the hyperbolic principle from the Maudsley guidelines is layered on top of Professor Ashton’s crossover.
To begin, contact Dr. Leeds through the contact form at drleeds.com. He sees patients throughout Florida by telemedicine.
This article is educational. It is not medical advice, and reading it does not create a doctor-patient relationship. Decisions about starting, continuing, or tapering any medication should be made with your own physician.
About the physician
Mark Leeds, D.O. is an osteopathic physician providing concierge telemedicine care focused on benzodiazepine and z-drug tapering and psychiatric medication deprescribing. He serves on the medical advisory board of the Benzodiazepine Information Coalition and hosts The Rehab Podcast on the Mental Health News Radio Network. He is accepting new patients for telemedicine visits throughout Florida.
