Why does Xanax cause anxiety between doses?
Because it wears off before the next dose is due. Xanax, or alprazolam, is a short-acting benzodiazepine: Table 1 of the Ashton Manual gives it a half-life of 6 to 12 hours, and the alprazolam label reports a mean of 11.2 hours with a range of 6.3 to 26.9 hours.
Taken two or three times a day, a drug that leaves that quickly lets the blood level rise after each tablet and fall well before the next one. In a body that has adapted to the drug, that fall is felt, and the adaptation itself is physical dependence. Dependence is not addiction.
Chapter II of the Manual describes the peaks and troughs between doses of alprazolam, and says that many people experience a “mini-withdrawal” between each dose. The label itself reports early morning anxiety, and anxiety emerging between doses, in people with panic disorder taking prescribed maintenance doses.
A common pattern is the person who takes a tablet at breakfast, mid-afternoon, and bedtime, and by late morning is restless, tense, and watching the clock. It looks like the anxiety getting worse. It is the last dose running out.
That person took the medication exactly as prescribed, and their body adapted to it. The clock-watching is a sign of the drug’s half-life, not of a character problem.
Interdose withdrawal happens on a steady dose, before any taper begins.
Unfortunately, the two are easily confused. Interdose withdrawal is the return of symptoms between scheduled doses at a dose that has not changed, while withdrawal from a taper is the response to a reduction. A person who mistakes the first for worsening anxiety may be given a higher dose, and a person who mistakes it for taper failure may give up a taper that was going well.
The timing is what tells them apart. Interdose withdrawal arrives at about the same number of hours after each dose and eases once the next tablet is taken, while withdrawal from a reduction follows the reduction and does not track the clock. A week of brief notes on dose times and symptom peaks gives the prescriber that pattern.
Why does the Ashton Manual switch Xanax to diazepam?
Because diazepam leaves the body slowly. Table 1 gives diazepam a half-life of 20 to 100 hours, with an active metabolite that lasts 36 to 200 hours, so its level from one dose hardly moves before the next. Professor C. Heather Ashton chose it for that property, and because it comes in small strengths, including 2 mg tablets that halve to 1 mg.
Alprazolam behaves like a wave machine, the level rising after each tablet and dropping before the next. Diazepam behaves like a lake. The level moves, but so slowly that the surface looks flat from one dose to the next, and a lake can be lowered an inch at a time.
The method is Professor Ashton’s, and this site presents it as hers. Diazepam is not substituted because it is a better anxiety drug, but so that the reductions can be small, even, and felt gently.
How much diazepam equals a dose of Xanax?
The Manual’s equivalence table treats alprazolam 0.5 mg as approximately equivalent to diazepam 10 mg, and the footnote matters as much as the figure: the equivalents are “firmly based on clinical experience but may vary between individuals.” It is a planning figure, not a prescription. The Ashton Manual’s equivalence table, explained covers the rest of the table.
The arithmetic shows why. A person taking 1 mg three times a day is taking 3 mg of alprazolam, which the table would put near 60 mg of diazepam. Treating the two medications as interchangeable milligram for milligram would be a serious error.
Yet, the Manual does not treat the full equivalent as a target to be reached in one move. A person switched suddenly to the whole equivalent is liable to become extremely sleepy, it warns, while one moved to an inadequate dose gets withdrawal symptoms, and many people have suffered that way. Substituting one dose at a time avoids that dilemma and, in the Manual’s words, helps to find the equivalent dosage for that individual.
How does the stepwise substitution work in practice?
The Manual’s instruction is short. The switch-over is carried out gradually, in stepwise fashion, substituting one dose at a time, usually starting with the night-time dose, and the substitution may not always need to be complete. The other doses stay unchanged while one is converted, and the next one moves at an interval of a few days or a week.
Starting at night is practical, since any early drowsiness from diazepam lands at bedtime. Each substitution is also a test: if the person is oversedated, the equivalent was generous for them, and if withdrawal shows through, it was lean. The prescribing physician reads that from brief daily notes on sleep and symptoms, and adjusts before the next dose moves.
The Manual’s worked alprazolam schedules, from 6 mg a day and from 4 mg, run their stages at one to two weeks each. The 6 mg schedule’s note says its first four stages involve no actual withdrawal, only substitution, its diazepam reductions begin while alprazolam is still being taken, and partway through it moves to twice-daily dosing.
So, the Manual does not switch everything at once, wait two weeks, and then start reducing. An overnight change of a whole day’s alprazolam to 40 mg or more of diazepam is a different and more sedating approach, not the Manual’s. Stability comes from the pace of the crossover taper itself: by the time the last alprazolam goes, the diazepam has had weeks to settle and the swings have flattened.
How fast does the diazepam come down afterward?
The Manual’s rule is to aim at reducing by up to one tenth at each decrement. Its own example runs from 40 mg of diazepam a day, or its equivalent: 2 mg every week or two until 20 mg is reached, then 1 mg every week or two, and for some people 0.5 mg steps once they are down to 5 mg.
Those figures are the shape of the Manual’s example, not a schedule for any particular reader, and the actual steps belong to the person and their prescriber. Because the rule is a fraction of what remains, the steps shrink as the dose falls and the end is the slowest part.
That is the shape the Maudsley Deprescribing Guidelines later formalized as hyperbolic tapering, and Ashton Manual Guide reads the two as consistent rather than competing. The Alprazolam Taper Calculator and the Xanax Taper Calculator on this site lay that shape out as educational planning tools.
Holds are part of the plan, not a failure of it. The Manual says a person can stand still and take a vacation from further withdrawal for a few weeks, but should avoid ever increasing the dose again. In fact, it is equally plain about the other extreme: the last tablet is often dreaded, the final parting is usually easier than feared, and there is no virtue in stretching the last milligram out. In this site’s view, that suits people whose final steps go smoothly, but for many people the gentler ending is diazepam oral solution, at one milligram in each milliliter, reduced below half a milligram in proportionally smaller steps and stopped at about 0.1 mg.
Can Xanax be tapered without switching to diazepam?
Yes. Some people are already on a small dose and would find a crossover taper more disruption than help, some tolerate diazepam poorly, and the Maudsley Deprescribing Guidelines note that diazepam’s long-lived metabolite can accumulate in older adults and in liver impairment. The principles are the same, with a shorter-acting drug and more doses a day.
The obstacle is the tablet. The Manual points out that the smallest alprazolam tablet, 0.25 mg, is worth about 5 mg of diazepam, so at low doses each cut becomes a large fraction of the dose, which is why it mentions liquid preparations reduced by volume with a syringe and why compounding pharmacies in the United States prepare alprazolam suspensions. The choice between the two routes belongs to the person and their prescriber.
How long does the whole process take?
Months, and the Manual is unbothered by which number of months. Its estimate for the 40 mg diazepam example is 30 to 60 weeks, its worked alprazolam schedules state roughly 14 to 28 weeks from 6 mg and 22 to 37 weeks from 4 mg, and it says that whether withdrawal takes 6, 12, or 18 months is of little significance for someone who has taken benzodiazepines for years.
Unfortunately, the six-week withdrawal period adopted by many clinics and doctors is, in the Manual’s words, much too fast for many long-term users, and any fixed number of weeks promised before the person has taken a single step is a guess dressed as a plan. Fortunately, a taper that takes a year and holds along the way is still a taper that ends.
What if symptoms become severe during the switch or the taper?
The answer is to hold, and if holding is not enough, to slow the pace or return to the last steady step, with the prescriber. Severe symptoms during a crossover taper usually mean a step was too large or too soon, and the fix is the step, not the plan. What a person should never do is stop either drug outright to get it over with.
The alprazolam label carries the boxed warning that the 2020 United States Food and Drug Administration (FDA) label update placed on every benzodiazepine: abrupt discontinuation or rapid dosage reduction after continued use may precipitate acute withdrawal reactions, which can be life-threatening, and seizures are among them. The Manual says the same of over-rapid withdrawal, and adds that it may raise the risk of protracted withdrawal, the months-long symptoms it estimates affect perhaps 10 to 15 percent of long-term users.
Call 911, or local emergency services, for a seizure, for severe confusion or hallucinations, or for any medical emergency. Anyone in crisis or thinking about suicide can call or text 988, the Suicide and Crisis Lifeline.
Questions readers ask about switching from Xanax to diazepam.
Why is diazepam better than Xanax for tapering?
Because it lasts. Diazepam’s 20 to 100 hour half-life keeps the level nearly flat between doses, while alprazolam’s 6 to 12 hours lets withdrawal return before the next tablet, and diazepam’s small scored tablets allow finer reductions.
How long does the Xanax to diazepam switch itself take?
There is no fixed timetable. Each dose crosses over at an interval of a few days to a week, and the Manual’s worked schedules spread the stages across a few months while the reductions begin.
The switch is a way off benzodiazepines, not a new home.
Tolerance and dependence apply to diazepam exactly as they apply to alprazolam, and a person parked on the substituted dose for years has changed tablets, not situations. The point of the crossover taper is the taper.
What matters is a prescriber who slows the taper when it is too fast and agrees to a little more speed when it is going well. The Ashton Manual diazepam switch covers the other short-acting benzodiazepines, and Xanax withdrawal anxiety covers the symptoms and their timeline.
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.
