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Hallo. I have been on Paxil for 20 years, 20 mg I went down to 10mg, then I switched to Prozac After 15 months tapering, I am down to 1 mg In my country there is no liquid for Prozac, but I can resolve them in water, just don’t know how to measure. I would appreciate a help with that. Thank you

PLEASE READ THIS ENTIRE TOPIC BEFORE GOING OFF PRISTIQ. Pristiq comes in insufficient dosages to taper. Do not alternate doses of Pristiq to taper -- this will cause the levels of this medication in your brain to go up and down and is second only to cold-turkey in causing withdrawal symptoms. AND DON'T COLD-TURKEY EITHER!!!!!!!!! To reduce the risk of withdrawal symptoms and post-discontinuation prolonged withdrawal syndrome, as with other psychiatric drugs we recommend reducing Pristiq by 10% per month, calculated on the last dosage. (The amount of the reduction gets progressively smaller.) See Why taper by 10% of my dosage? The official prescribing information from the FDA contains this: However, Pristiq is difficult to taper "at a more gradual rate" as it comes in only 3 dosages: low, average and excessive -- and officially, the tablets cannot be split. PROTEST THIS DANGEROUS DRUG Phone Pfizer, Pristiq's manufacturer, to make a complaint: (800) 438-1985 in the US Pfizer has not provided any specific information on how to taper from a dosage of 25mg Pristiq, the lowest available dosage. They may suggest alternating dosages to taper Pristiq. Don't do this -- it's like playing ping-pong with your brain. File a complaint about the difficulty of tapering off Pristiq -- the range of dosages is inadequate. Also complain to the FDA 1-800-FDA-1088 Mon–Fri between 8:00 a.m. and 4:30 p.m. EST. Pristiq is Effexor's fancier sibling Pristiq is a drug made of Effexor's (venlafaxine) active metabolite, O-desvenlafaxine. Pristiq is to Effexor as Lexapro is to Celexa -- a tweaked and more powerful isomer molecule. In effect, Pristiq is concentrated Effexor. See http://www.primarypsychiatry.com/aspx/articledetail.aspx?articleid=2464 According to Pfizer http://labeling.pfizer.com/showlabeling.aspx?id=497, Pristiq is available in extended-release tablets of 25mg, 50 mg, and 100 mg; the most common dosage is 50mg. Unlike Effexor, which is metabolized primarily by liver enzyme P450 CYP2D6, Pristiq is metabolized via conjugation and liver enzyme P450 CYP3A4. It attains peak plasma concentrations in about 7.5 hours. As a chemical, before it's put into an extended-release tablet, desvenlafaxine has a half-life of around 11 hours. Pristiq's extended-release formulation According to this paper, the extended-release formulation releases desvenlafaxine over 24 hours. The mean half-life of desvenlafaxine, without the extended-release formulation, is around 11 hours. The extended-release formulation is a monolithic matrix -- it's in the glue that holds the tablet together, not in the coating. I confirmed this in a phone conversation with Pfizer medical information (1-800-438-1985). (Thank you, oaklily, for this information about the matrix formulation.) Rather than a timed-release coating, the coating on the Pristiq tablet is only protective. The extended-release mechanism is part of the tablet matrix, or the glue that holds the tablet together. This is called a monolithic matrix tablet. If the tablet is split, the matrix is damaged and may not reliably be extended-release, depending on the size of the fragments. Larger fragments are more likely to retain some extended-release capability. When the tablet is CRUSHED, the matrix is completely destroyed. The particles should be assumed to have NO extended-release capability. A Pristiq fragment becomes desvenlafaxine, with an 11-hour half life. (Here is a description of the similar matrix formulation for quetiapine XR (Seroquel XR) .) OPTIONS FOR TAPERING PRISTIQ Since medicine knows nothing about tapering Pristiq, the following are all informal suggestions. Try any of them at your own risk. Please let us know how you do by posting in this topic. Cut up Pristiq tablets Despite the warnings not to cut it up, from reports on the Web, cutting up Pristiq tablets does seem to work for some but it makes others ill, possibly because of "dose dumping." According to Pubmed on Desvenlafaxine: "....The extended-release tablet does not dissolve in the stomach after swallowing. It slowly releases the medicine as it passes through your digestive system. You may notice the tablet coating in the stool...." The extended-release mechanism is part of the tablet matrix, or the glue that holds the tablet together. If the matrix is destroyed, the entire dose is released at once or "dumped," instead of being gradually released through the matrix formulation. Without the extended-release matrix, a Pristiq fragment becomes desvenlafaxine, with an 11-hour half life. To avoid "dose dumping" of the entire dose, you might take smaller divided doses of Pristiq, more than once a day, like immediate-release Effexor, to mimic an extended-release dose. Cut-up Pristiq seems to sometimes cause stomach upset, which may be reduced by taking it with food. Now that the 25mg tablet is available, cutting it into quarters gives you the option to taper by 6.25mg per step. If you are taking 100mg Pristiq or 50mg Pristiq, you may wish to request part of your prescription be written for 25mg tablets. (For insurance coverage of multiple dosages, your doctor most likely will have to specify taking Pristiq in "divided doses.") You may find you need a precise way to measure your tablet fragments. See Using a digital scale to measure doses As you get down to a low dose, you may wish to switch to Effexor to more precisely control dosage decreases, see below. Reducing from 100mg Pristiq to 50mg Pristiq Drug switches incur additional risk. Before trying a switch to Effexor or Prozac (fluoxetine) from 100mg Pristiq, it's probably wise to go down to 50mg Pristiq first, or 25mg if possible. Combining whole tablets, with their extended-release qualities, with tablet fragments probably makes "dose dumping" less likely or noticeable. You might use a 50mg tablet plus a 25mg tablet plus 3/4 of a 25mg tablet (18.75mg) to make the first reduction to 93.75mg 2nd reduction: a 50mg tablet plus a 25mg tablet plus 2/4 of a 25mg tablet (12.5mg) to go to 87.5mg 3rd reduction: a 50mg tablet plus a 25mg tablet plus 1/4 of a 25mg tablet (6.25mg) to go to 81.25mg 4th reduction: a 50mg tablet plus a 25mg tablet to go to 75mg 5th reduction: a 50mg tablet plus 3/4 of a 25mg tablet (18.75mg) to go to 68.75mg 6th reduction: a 50mg tablet plus 2/4 of a 25mg tablet (12.5mg) to go to 62.5mg 7th reduction: a 50mg tablet plus 1/4 of a 25mg tablet (6.25mg) to go to 56.25mg 8th reduction: a 50mg tablet If withdrawal symptoms occur, some people have found taking an additional fragment of a tablet can smooth the transition from one dosage to another. Another way to get from 100mg to 50mg or 25mg is to combine Pristiq tablets with a liquid made from immediate-release Effexor (see below). Once at 50mg or 25mg, stabilize for a month at least and consider your plan for the next stage of tapering. Have Pristiq made into smaller dosage capsules or a liquid by a compounding pharmacy Compounding pharmacies can crush the tablets and put the powder into smaller capsules by weight. Like cutting up tablets or crushing, this destroys the time-release quality, but the compounded method is much more exact. In your body, crushed Pristiq is similar to regular immediate-release Effexor, with an 11-hour half-life. You may wish to have your dose compounded to take twice a day. If you are taking 50mg Pristiq, for example, you would have 60 capsules compounded per month. Each capsule would be 1/2 of 45mg (a 10% reduction of 50mg) or 22.5mg. You would take two capsules per day, once in the morning, and once in the evening. The next month, you would have 60 capsules compounded, each capsule being 1/2 of 40.5mg (a 10% reduction of 45mg) or 20.25mg. And so forth, for each reduction. (According to my compounding pharmacy, they can put in a slow-release additive distributing absorption over 8-10 hours. This is not as long as the Pristiq time-release coating, but at least it's something. Check with your compounding pharmacy about this. See getting-custom-dosages-at-compounding-pharmacies-us-uk-and-elsewhere ) If this does not work, you may wish to switch to Effexor XR and use the bead-counting method. Regular Effexor probably wouldn't be an advantage over Pristiq compounded to custom dosages. One of our members had a desvenlafaxine liquid made by a compounding pharmacy. Most likely, this compounder used pure desvenlafaxine succinate powder to make this liquid, as desvenlafaxine tablets contain a glue that might resist being made into a liquid. But he may have a way to grind tablets up to make a suspension. A liquid would have to be immediate-release, with a half-life of around 11 hours. Generally, you'd take a drug with that short a half-life twice a day. Crush Pristiq tablets, weigh powder with a digital scale This is similar to cutting up tablets -- Pristiq is a "do not crush" medication, as it is a time-release drug. The Pristiq powder becomes desvenlafaxine, with an 11-hour half life. If you pulverize the tablet, you might take smaller divided doses of Pristiq, more than once a day, like immediate-release Effexor, to mimic an extended-release dose. In principle, this would be a more precise way of tapering than cutting up tablets: Crush the tablet Make sure the shell fragments are evenly distributed in the powder Weigh the powder for a dose with a digital scale Put the powder into an empty gelatin capsule to make it easier to ingest Peer discussion of this method starts here http://survivingantidepressants.org/index.php?/topic/876-tips-for-tapering-off-pristiq-desvenlafaxine/page__view__findpost__p__27417 Switch to Effexor or Effexor XR Note: If you've had an adverse reaction to Effexor before, do NOT switch from Pristiq to Effexor. "Desvenlafaxine (O-desmethylvenlafaxine) is the major active metabolite of venlafaxine." Since the relationship is so close, switching to regular immediate-release Effexor tablets, which you can cut up or make into a liquid, this may be the best way to taper off Pristiq. Because it has a mean half-life of 5 hours, you'd have to take regular Effexor twice a day. Alternatively, you might substitute Effexor XR, which is released gradually like Pristiq and needs to be taken only once a day. You'd have the difficulty of tapering off Effexor or Effexor XR -- themselves notorious for withdrawal difficulties -- but at least you can do that gradually. See Tips for tapering off Effexor and Effexor XR (venlafaxine). According to FDA Prescribing Information for venlafaxine (Effexor), the usual dose of Effexor is 150mg per day. Since 150mg Effexor and 50mg Pristiq are both "normal" dosages of their respective drugs, they may be roughly equivalent. (If you've just quit Pristiq and are experiencing withdrawal symptoms, you may wish to reinstate a LOWER dose of Effexor XR, such as 37.5mg, to start. This may be enough to stop withdrawal symptoms and avoid a kindling reaction.) The psychiatrist who writes the 1boringoldman.com blog reports success in switching one patient from Pristiq to Effexor, then tapering Effexor, here (see comments) Another psychiatrist said when he tried this, the switch from Pristiq to Effexor was "seamless." Dr. Stuart Shipko posts here: Advice from a psychiatric pharmacist I have been corresponding with a professor at a prominent US university pharmacy department. Here is his best guess at how to taper Pristiq (he does not want his name published): Then taper off fluoxetine (Prozac). See Tips for Tapering Prozac Advice from Dr. Stephen Stahl, author of the manual Essential Psychopharmacology In his widely read psychopharmacology manual, eminent psychopharmacologist Stephen Stahl advises titration by crushing the tablets and mixing in fruit juice, see http://survivingantidepressants.org/index.php?/topic/876-tips-for-tapering-off-pristiq-desvenlafaxine/page__view__findpost__p__14799 According to our member oaklily, Stahl is wrong. Making a liquid from Pristiq does not work, see http://survivingantidepressants.org/index.php?/topic/876-tips-for-tapering-off-pristiq-desvenlafaxine/page__view__findpost__p__24822 Dr. Stahl intends to correct his book, according to this correspondence 09/15-9/16/13 with him: Use a combination of Pristiq tablets and Effexor liquid Pristiq cannot be made into a liquid, but its close relative immediate-release Effexor (not Effexor XR) can. You may be able to go off Pristiq by taking part of your dose in lower-dose tablets and part in liquid Effexor, gradually converting to all-liquid Effexor as you get to lower dosages. This may offer a convenient and gradual path off Pristiq. Only regular immediate-release Effexor can be made into a liquid (see Tips for tapering off Effexor (venlafaxine) ). As immediate-release Effexor has a short half-life and is usually dosed twice a day, you may wish to take the liquid portion of your dosage later in the day. For example, if you are taking 100mg Pristiq, you may wish to take your daily dose as one 50mg tablet and the rest later in the evening as a liquid made from immediate-release Effexor. You can titrate the liquid by 10% of your daily dosage to taper until you get to 50mg. Then you can take a 25mg Pristiq tablet with the rest in a liquid made from immediate-release Effexor. When you get to 25mg Pristiq, you might switch to splitting the tablet and taking the rest in Effexor liquid and so on until you are taking only liquid Effexor. To do this, you will have to request a prescription for Effexor tablets as well as Pristiq from your doctor. "Bridging" with Prozac or another antidepressant Any drug change incurs additional risk. A switch to Prozac from Pristiq may not work -- they are very different drugs -- or you might have adverse reactions to Prozac. Prozac is regularly used to "bridge" off Effexor. Given that Pristiq is a sibling of Effexor and Effexor XR, it is possible that one can, similarly, use Prozac to withdraw from Pristiq. Attributed to Joseph Glenmullen, the "bridging" technique is described by a doctor here http://www.bipolarworld.net/Phelps/ph_2005/ph1354.htm Read this entire topic before attempting a switch to Prozac: The Prozac switch or "bridging" with Prozac Later, taper off Prozac. At least Prozac comes in a liquid. To do this, consult a doctor knowledgeable about this technique.