I have stopped taking Pristiq 50mg. per day and have been put on Effexor at 225 mg per day - what dosage of Effexor is required to equal 50mg. of Pristiq?
What is an equal dosage of Pristiq 50mg 1 daily and Effexor?
Question posted by paulc451 on 22 April 2013
Last updated on 4 May 2015
Added 23 April 2013:
I have been diagnosed with Chronic Depression and Anxiety Disorder.
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7 Answers
Carol Jane
26 March 2015
My son was taking 50 MG Prestiq and was replaced with
150 Mg of Venlafaxine (Effexor)
paulc451
10 Aug 2014
Thanks everyone for all of your replies in trying to figure out the mystery of what is comparable. My psychiatrist and I agreed that the dosing he was headed for and which I reached with Effexor was the max dose and bottom line, was way too much. I had a horrible experience with Effexor because the dosing we went to was too high. I think we decided I probably could have started at 75, gone to 150 and had a similar effect as Pristiq. We went to the max of 325 mg per day and it was actually dangerous because my blood pressure went through the roof, I was hallucinating and every other side effect you read about I had. I ended in June last year when I took myself back to 225 and made an appointment to see him. I walked in his door and he had a taper off the Effexor schedule ready, 18 weeks or free samples of Pristiq and a graduation schedule to get back on it with a promise that between the two of us we would get Pristiq covered.
It took 2 appeals but before the 18 weeks was up, the Pristiq was covered and I have been back on it for over a year and am doing amazingly well. So I guess based on that, there really isn't a need to comment any further unless it's helping someone else in a similar situation. As for me, I am where I want to be with medications that after 15 different ones to treat the chronic depression and General Anxiety disorder have allowed me to function relatively normally. I am still on a cocktail but it is minimal. I now am on 50 mg Pristiq, 7.5 mg of Mirtazapine and up to 5 - .5 mg of clonazepam per day although if I take 3, I'm having a bad day. I am no longer trapped in my house, have no drug hangovers at all, don't have difficulty with sleep, am doing a ton of volunteer work, getting a ton of exercise and am basically controlled and happy. It took 9 years to get here but for those who have read this thread and are having difficulty still finding a cocktail that works for you, keep the faith and you will eventually find what works best for you. Good luck everyone and thanks again. Over an OUT! Paul... :)
DBMD89
8 Aug 2014
About 55% of a single dose of venlafaxine ER (Effexor XR) is converted to desvenlafaxine (Pristiq). The metabolite of the latter is of little clinical consequence. Both are SNRI's (serotonin-norepinephrine reuptake inhibitors). The ratio of serotonin to norepinephrine reuptake for venlafaxine ER is roughly 1:30, whereas for desvenlafaxine it is 1:16 (for the other SNIR's - duloxetine (Cybalta) it is 1:9 and for levmilnacipran (Fetzima) it is 1:0.6). Keep in mind the venlafaxine ER really does not become fully effective as an SNRI till a dose of 225 mg is reached. At the starting dose of 75 mg it acts as a SSRI. The two are NOT the same drug, but rather the parent compound, venlafaxine, is metabolized to desvenlafaxine. Put differently, if you are taking Effexor XR you are also taking Pristiq, but not vice-versa.
There is no simple equation for converting equivalencies, though one might make an informed guess that if 55% one dose of venlafaxine ER is metabolized to desvenlafaxine, then maybe a little less than twice as much of the former would be needed. It is best to work out with your doctor based on the clinical effectiveness of either compound.
minustart
29 Oct 2013
Paulc451,
I realize this question was from much earlier in the year, but I would like to let you know, that the same thing happened to me. I was on Pristiq 50 mg Extended Release Tablet once a day. I couldn't afford to pay for the medication, so my doctor was giving me his samples. He ran out 2 months ago, and started me on Effexor. The reason for creating Pristiq and the reason it worked so well for me was because it gives the same effectiveness of Effexor, but without the side affects. He now has me on Venlafaxine (Effexor) XR 150 mg, which IS the equivalent to 50 mg of Pristiq. I do notice the side affects more which has a tendency to bring me down a little bit because it makes me very tired at times, but my severe depression and anxiety has still been better than it has been in years.
I'm on a combination of Bupropion (Wellbutrin) 200 mg a day, Clonazepam 2 mg a day, Trazodone 200 mg at night time (its helps with insomnia) and the Effexor, which I take in the morning. I hope, if you haven't been helped yet, this will help a little.
paulc451
29 Oct 2013
That was definately helpful minustart. Based on what you've said, it would appear my psychiatrist was being aggressive in attempting to find an equal dose by starting me out at 225mg. Perhaps 150mg would have been a better place to start but it's history now if you read my previous post. We tried Trazadone with the Pristiq for sleep but it made me really hung over in the morning so we switched to a very low dose of mertazapine which helps. My psychiatrist believes I don't metabolize some drugs well which is why the trazodone made me feel hungover. After 8 years and all the medications I was taking or have been on (15 in total) and and feeling non-functional, not so much because of my diagnosis but because of the effects of the drugs, I told my psychiatrist, which was new at the time, that I would sooner suffer the symptoms than be non-functional.
The low dose of mertazapine started at 15mg but I still felt hung over the next day so it's now 7.5 mg per day and that is just enough. I also can take up to 2.5 mg of Clonazepam a day although I generally take 1 to 1.5 which seems to be all I need. Thanks again for posting this minustart!
cynergie
6 Feb 2014
Paulc451 I also was on 225mg of effexor and it stopped working. My psychiatrist put me on pristiq 50mg for severe depression and panic attacks. I was also wondering what is the equivalent of the two meds. Also did you experience any withdrawal symptoms when you switched? I had some brain zaps and headaches.
Inactive
23 April 2013
Hello paulc 451. If you might please add onto your question the/your diagnosis. Regards pledge
paulc451
29 Oct 2013
My diagnosis is Chronic Depression and Generalized Anxiety Disorder. Since my original posting, I went through 3 different dosings of Effexor and it, for me, is a demon drug. My symptoms at 225 mg started to re-appear. We upped the dose to 300mg for 6 weeks and the symptoms got worse plus I started having side effects to the drug (drug hangover, dizziness, increased anxiety, confusion, difficulty with memory etc.) after 6 weeks we went to 375mg. My symptoms peaked where I was having outright panic attacks again, became agoraphobic, and the side effects including blood pressure which spiked from normal to 146/90, hallucinations, major drug hangover etc. At that point, my psychiatrist took me off Effexor gradually over a short period of time and reintroduced 50 mg. of Pristiq. I stopped the Effexor completely in June. He provided me with 18 weeks of samples because none of my benefits would cover the cost of Pristiq which was the initial reason for the switch to Effexor.
Fortunately, after 2 appeals with one benefits provider, they agreed to cover the cost. I have been on 15 different medications over the last 8 years and Pristiq is the only one that has had any positive results to the point that I can function. Effexor out of all 15 is the worst drug I have ever taken and as a result, Pfizer has included me in a study on the safe use of the drug. It's now October and I am still having long term side effects to the Effexor. I know for some the drug has been a miracle and I'm happy it's worked for them but not for me, it was a nightmare and continues to linger - nothing major but enough to know some of the side effects are hanging on.
cynergie
10 Aug 2014
Hi Paulc451. I was on effexor and had ongoing symptoms of chronic depression and anxiety. I had a dose of 225mg. she switched me to Pristiq 50mg with huge improvement. Since then she raised it to 100 mg since a family tragedy, which I can not handle the way normal folks do. So I'm doing great, never going back to effexor. Gool luck to you.
geezloueez
4 May 2015
Hi paulc, isn't it crazy that the Pristiq is considered an active ingredient of Effexor so doctors do consider them almost the same drug... yet they can have SUCH a difference in reaction in the brain!!! I have depression and it kicked in after having my kids and post partum depression and a whole lot of hormone treatment for endo prior to kids!! Anyways I was taking the tiny dose of Effexor for 7 years and all of a sudden 2 years ago it decided to stop working and I had some big stressers in my life and the big black cloud and tears and lack of motivation came in... I'm now doing the drug dance to see which one does the trick to help feel "normal" as I can!! From SSRI's to SNRI's to which one dose the trick!!! Crazy rollercoaster that's for sure.
LaurieShay
22 April 2013
Pristiq and Effexor are very similar but not the same. Pristiq is desvenlafaxine, while Effexor is just venlafaxine. It is very difficult to equate one antidepressant to another in terms of dosage. You were taking the normal therapeutic amount for Pristiq, Effexor can go as high as 375mg so 225 isn't too far off looking at it this way. You are going to experience some withdrawal symptoms from the Pristiq and some side effects as you get use to the Effexor (even though they are similar). Be patient and the Effexor should be working within a month.
kaismama
22 April 2013
Thank you Laurie after the attack i was beginning to think I'd list my mind.
paulc451
22 April 2013
Thank you for your comment. I have been off Pristiq since mid Feb and on the dose of 225mg or Effexor since early March - it was a 9 week process to get to get off the one while introducing the other. What I do know is the dosage I am of Effexor isn't doing even close to what the Pristiq was doing. My psychiatrist told me it was a similar drug which metabolized differently than the Pristiq and dosing would be the problem attempting to get the same effect. The pharmacist I asked today told me the dose I was on of Effexor was actually lower than what would be normal for 50mg of Pristiq daily so I was just wondering if anyone knew or had made the same switch and what dose of Effexor they took in order to achieve the same results. If I can go as high as 375 then there is some hope I guess that I will get back to where I was on Pristiq.
As I think I said before, the only reason for the change was that I was being supplied free samples of Pristiq for over a year and it couldn't continue but none of my benefit plans would cover the cost. The reason it is not covered is because they indicated in both plans that the same drug is already approved for use in Ontario. Thanks again for your response but I'm getting impatient because it's been over a month since I have been on 225 mg and symptoms, although not as severe, have returned and sometimes as severe as they were prior to Pristiq. You should also know that Pristiq was the first drug after 11 attempts at other drugs over the last 12 years that actually worked well in conjunction with 1 other antidepressant and a benzodiazepine.
LaurieShay
22 April 2013
Time to let the doc know that the 225mg Effexor is not enough to keep your symptoms at bay.
paulc451
22 April 2013
You're right Laurie - unfortunately we only have 2.5 psychiatrists where I live and I can't get in to see him until May 16 and there is no cancellation list unfortunately. We had discussed it would be a process and it has been for sure but unfortunately getting in to see him any sooner, and God knows I've tried... :) just isn't possible. I can live with the symptoms - I have for 12 years, but prefer not too if the dosage can be tittered to an amount that was as effective as the Pristiq. It just means there are days where I do nothing again from time to time and that constant "unwell" feeling is always there. It will work itself out I'm sure but it's a much longer process than I was hoping for...
LaurieShay
22 April 2013
unfortunately it can be a long ordeal changing meds. Hang in there and here if you need to talk.
paulc451
22 April 2013
Thank you - I really am ok - just not as good as I was and after being on so many different meds over the 12 years - at one point for a period of 5 years, and with a different psychiatrist, I was on 4 antidepressants at the same time as well as a benzodiazepine. I took myself off of everything at one point and decided I was either going to live with the depression and anxiety and not let it control me, or I wasn't. I was semi successful with no meds for 9 months and although my head was much clearer, the symptoms gradually returned. I went to the new psychiatrist and we have an agreement to work together to make things right without over doping me which was occurring with the previous Dr. Pristiq was a miracle drug for me but sleep was still an issue (2 - 3 hours per night) and I started to develop upper muscular back problems which were related to the anxiety.
The sleep was supposed to be helped by adding the additional anti-depressant Mirtazapine and the addition of Clonazepam (even though I said I wouldn't go the benzodiazepine route again he convinced me after much discussion), 4 times daily with the largest dose (3 - .5 mg at bedtime) but I still had problems sleeping although my back did ease up somewhat. The sleep thing I can live with - or in this case without - it could be better if I could find more to do when I'm not sleeping mind you - because again, it's been years, but now I'm my back is almost where it was pre-Pristiq and the addition of clonazepam, which I am still taking. I'm just frustrated big time at this point because of the length of time the change over is taking and the length of time I have to wait to see my psychiatrist. I had to stop doing a day a week doing some volunteer work I was doing because of the return of the symptoms especially being away for a long period of time although for most a full day isn't a long period of time. I'm still doing all the other stuff that I can but it is in shorter periods of time and not as frequent so I still feel somewhat in control but it's when the symptoms I hide really well decide I can't hide them that day that frustrates me and it's happening more frequently than when I was on Pristiq. Anyway - that's enough for now - thanks for listening and being supportive. I will keep you posted as things progress... :)
LaurieShay
22 April 2013
Please keep me updated. I know the frustration about taking many meds. I take 5 for psychiatric reasons and though I consider myself functioning very well, it hasn't always been this way.
paulc451
23 April 2013
Will do Laurie - I have been on disability which also frustrates me being a social worker - who is harder to help than a helper - and have been told by this psychiatrist that based on the history and the extremes I go through with the anxiety in particular, the chances of getting back to work any time soon are really slim. But, I do what I can and was adding a bit more as I felt up to it then the change over and having to pull back makes me feel I'm not functioning as well, but still functioning never-the-less. Sorry you're on 5 different meds - that may seem like a lot, but if you THINK you're functioning, then you ARE functioning and that's a good thing! Kudos to you!
LaurieShay
23 April 2013
Thanks!!
paulc451
23 April 2013
No problem - sounds like you're doing really well under the circumstances and thanks to you for letting me ramble which I tend to do and offering your comments. It's very much appreciated...
LaurieShay
23 April 2013
Stay in touch!!
paulc451
23 April 2013
will do!
kaismama
22 April 2013
You really don't compare them, 225 mg of effexor is a high dose of effexor. I've taken150 for the past 10 yrs.
paulc451
22 April 2013
It's the same drug therefore the dose is comparable to be sure I am taking an equal amount of Effexor (Venlafaxine) as I was taking of Pristiq. 225mg per day of Effexor is apparently the max dose but according to the pharmacist today, it is actually a lower dose of Venlafaxine as when I was taking 50mg of Pristiq daily. So, yes, it has to be compared to determine the correct dose to get me back to feeling like I was when taking Pristiq. No drug plans will cover Pristiq in Canada under any circumstances because Effexor is covered and is the same drug thus the switch over from free samples (Pristiq) to Effexor.
kaismama
22 April 2013
They aren't the same drug. Max dose of effexor is 375 and there I'd only one dose of pristiq, so how would you compare it. You can't say your taking a hi dose of pristiq or a low dose.
minustart
29 Oct 2013
kaismama, they ARE basically the same medication. Both the doctors and pharmacist do compare them as the same medication, with one exception being side effects. And there is a comparable dose: Pristiq (Desvenlafaxine Succinate) 50 mg Extended Release tablet = Novo Venlafaxine XR (Venlafaxine Hydrochlo) 150 mg L.A. capsule. This is the equivalent both my doctor and pharmacist gave me. I too am from Canada and have a government drug card that doesn't pay for Pristiq (not even co-pay), and I was receiving samples from my doctor who ran out of samples a few months ago.
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