BENZODIAZEPINE EQUIVALENCE TABLE - 1
Revised April 2007
This Benzodiazepine Equivalence Table is based on the extensive research and clinical experience of Professor C Heather Ashton, DM, FRCP, Emeritus Professor of Clinical Psychopharmacology at the University of Newcastle upon Tyne, England.
Sources: NRHA Drug Newsletter, April 1985 and Benzodiazepines: How they Work & How to Withdraw (The Ashton Manual), 2002. The approximate equivalent doses to 10mg diazepam (Valium) are given.
| Benzodiazepines1 |
Half-life (hrs)2
[active metabolite] |
Approximately Equivalent
Oral dosages (mg)3 |
Market Aim4 |
Alprazolam
(Xanax, Xanor, Tafil) |
6-12 |
0.5 |
a |
Bromazepam
(Lexotan, Lexomil) |
10-20 |
5-6 |
a |
Chlordiazepoxide
(Librium) |
5-30 [36-200] |
25 |
a |
Clobazam
(Frisium)5 |
12-60 |
20 |
a,e |
Clonazepam
(Klonopin, Rivotril)5 |
18-50 |
0.5 |
a,e |
Clorazepate
(Tranxene) |
[36-200] |
15 |
a |
Diazepam
(Valium) |
20-100 [36-200] |
10 |
a |
Estazolam
(ProSom, Nuctalon) |
10-24 |
1-2 |
h |
Flunitrazepam
(Rohypnol) |
18-26 [36-200] |
1 |
h |
Flurazepam
(Dalmane) |
[40-250] |
15-30 |
h |
Halazepam
(Paxipam) |
[30-100] |
20 |
a |
Ketazolam
(Anxon) |
30-100 [36-200] |
15-30 |
a |
Loprazolam
(Dormonoct) |
6-12 |
1-2 |
h |
Lorazepam
(Ativan, Temesta, Tavor) |
10-20 |
1 |
a |
Lormetazepam
(Noctamid) |
10-12 |
1-2 |
h |
Medazepam
(Nobrium) |
36-200 |
10 |
a |
Nitrazepam
(Mogadon) |
15-38 |
10 |
h |
Nordazepam
(Nordaz, Calmday) |
36-200 |
10 |
a |
Oxazepam
(Serax, Serenid,
Serepax, Seresta) |
4-15 |
20 |
a |
Prazepam
(Centrax, Lysanxia) |
[36-200] |
10-20 |
a |
| Quazepam (Doral) |
25-100 |
20 |
h |
Temazepam
(Restoril, Normison,
Euhypnos) |
8-22 |
20 |
h |
Triazolam
(Halcion) |
2 |
0.5 |
h |
Non-benzodiazepines
with similar effects1, 6 |
|
|
|
Zaleplon
(Sonata) |
2 |
20 |
h |
Zolpidem
(Ambien, Stilnoct, Stilnox) |
2 |
20 |
h |
Zopiclone
(Zimovane, Imovane) |
5-6 |
15 |
h |
Eszopiclone
(Lunesta) |
6
(9 in elderly) |
3 |
h |
All these drugs are recommended for short-term use only (2-4 weeks maximum).
Half-life: time taken for blood concentration to fall to half its peak value after a single dose. Half-life of active metabolite shown in square brackets. This time may vary considerably between individuals.
These equivalents do not agree with those used by some authors. They are firmly based on clinical experience during switch-over to diazepam at start of withdrawal programs but may vary between individuals.
Market Aim: Although all benzodiazepines have similar actions, they are usually marketed as anxiolytics (a), hypnotics (h) or anticonvulsants (e).
In the UK clobazam (Frisium) and clonazepam (Rivotril) are licensed for use as anti-epileptics only.
These drugs are chemically different from benzodiazepines but have the same effects on the body and act by the same mechanisms.
BENZODIAZEPINE EQUIVALENCE TABLE - 2
From: Clinical Handbook of Psychotropic Drugs, 4th revised edition, Bezchlibnyk-Butler et al. editors (Clarke Insitute of Psychiatry, Toronto), Hogrefe & Huber.
| Benzodiazepine |
Comparative
dose |
| Alprazolam |
.5 |
| Bromazepam |
3.0 |
| Chlordiazepoxide |
25 |
| Clonazepam |
.25 |
| Clorazepate |
10 |
| Diazepam |
5 |
| Estazolam |
1 |
| Flurazepam |
15 |
| Halazepam |
40 |
| Ketazolam |
7.5 |
| Lorazepam |
1 |
| Nitrazepam |
2.5 |
| Oxazepam |
15 |
| Prazepam |
10 |
| Quazepam |
7.5 |
| Temazepam |
10 |
| Triazolam |
2.5 |
According to this chart, it shows Xanax (Alprazolam) as half the strength of Klonopin (Clonazepam). Ashton's chart shows Xanax equal to Klonopin, in dosage at least.
One more link that supports this from mental-health-today.com: http://www.mental-health-today.com/rx/benzo.htm
Quote: "Most equivalancy tables are based upon what dose will cause a similar therapeutic effect. I do not know how scientific the process used to determine these numbers, or if they are more anecdotal in nature. I understand though, that Ashton made a study of what dose of Valium was needed in substitution to ensure that her patients didn't suffer from withdrawal symptoms during the substitution process. Given that she carried out a proper study, and specifically for determining the most suitable dose of Valium to use in substitution, her figures must carry the most weight. It might be the case (although I don't know of a mechanism that would account for it) that the amount needed for the purposes of substitution might vary from the figures for a dose of similar therapeutic effect when not used in substitution. This might go some way to explain the differing figures between different authorities, but I am being rather speculative. One thing is for sure: different benzos have differing therapeutic strengths. One might be better for insomnia, and another for anxiety. So, you can expect some individual variability in the correct dose to use in substitution.
"On balance, I would suggest that people use Ashton's figures. If you feel after a few doses that they are a little high for you, then you might well adjust the amount of Valium you use in substitution - this is only sensible. I would caution though, not to take more than Ashton recommends, as the experience of this forum is that her substitution ratios seems to be enough for just about everyone. If you feel they are not high enough, allow more time between each substitution."
Colin - Benzo Buddies Support Forum
