Brand & Generic Names; Drug Classes

US brand name: Prozac
Generic name: fluoxetine

Other Forms: Prozac Weekly, Sarafem (for PMDD), oral solution (It’s minty fresh! Really, it tastes like mint-flavored mouthwash2.)

Class: Antidepressants, specifically a Serotonin-Selective Reuptake Inhibitor (SSRI)

1.  FDA Approved Uses of Prozac (fluoxetine)

  • Major Depression for adults.
  • Obsessive-Compulsive Disorder
  • Panic Disorder
  • Bulimia Nervosa
  • Premenstrual Dysphoric Disorder (as Sarafem)

2.  Off-Label Uses of Prozac (fluoxetine)

  • Fibromyalgia
  • Arthritis
  • Chronic Fatigue
  • Multiple Sclerosis
  • Bipolar Depression
  • Lupus
  • Headaches
  • Irritable Bowel Syndrome (IBS)
  • Premature Ejaculation

3.  Prozac (fluoxetine HCl) Pros and Cons

3.1  Pros

Prozac’s long half-life makes the issue of med compliance a little less of a big deal – hence the approval for depressed teenagers – and SSRI discontinuation syndrome is rarely anything like it is with other SSRIs, if it happens at all.

3.2  Cons

The sexual side effects and weight gain, if it happens, can be pretty bad.

4.  Prozac (fluoxetine HCl) Side Effects

4.1  Typical Side Effects of Prozac (fluoxetine HCl)

The usual for SSRIs – headache, nausea, dry mouth, sweating, sleepiness or insomnia, and diarrhea or constipation, weight gain, loss of libido. Most everything will go away after a week or two, but the weight gain and loss of libido might stick around longer. Or permanently. Although weight gain is a coin toss.

4.2  Not So Common Side Effects of Prozac (fluoxetine HCl)

Rash, ‘flu-like symptoms, anger/rage.

4.3  Prozac (fluoxetine HCl) Freaky Rare Side Effects

Bleeding gums, amnesia, anti-social reaction (oh, come on, like we’re not anti-social already), herpes (again, blaming the med for an STD), excessive hair growth, engorged breasts (a.k.a. porno boobs), involuntary tongue protrusion (according to the PI sheet / PDR one 77-year-old woman stopped sticking her tongue out at everyone after they stopped giving her Prozac (fluoxetine hydrochloride)).

5.  Interesting Stuff Your Doctor Probably won’t Tell You about Prozac (fluoxetine HCl)

Prozac isn’t such a hot idea for anyone with diabetes, and not because of potential weight gain, rather it messes with your glycemic control.


6.  Prozac (fluoxetine HCl) Dosage and How to Take Prozac

Depression – 20mg in the morning, increasing by 20mg a day after at least a week, taken either in the morning or at noon until a maximum of 80mg a day is reached.

OCD & Bulimia – 20mg in the morning, increasing by 20mg a day after at least a week, taken either in the morning or at noon until a maximum of 60mg a day is reached.

Panic – 10mg in the morning. Increase to 20mg, either all in the morning or split into morning and noon. Hold there for awhile before increasing. Although you can go up to 60mg a day, few people responded to anything above 20mg a day.

Like any SSRI I recommend starting out with half the recommended dosage (except for Panic, that’s as low as you can get) and then increasing to 20mg after a week. If you don’t feel anything go up to 30mg, but stay there until you’ve given it a try for a month, otherwise it’ll just be a pain in the ass to stop it. Even at 30mg you’ll know after a month if it’s going to do something for you.

Prozac Weekly – You just take the one capsule a week for everything. That’s it.

7.  How Long Prozac Takes to Work

Like all SSRIs anywhere from a couple days to over a month. If you don’t feel any positive benefit after six weeks, then you should talk to your doctor about either another SSRI or trying a med that hits another neurotransmitter. Because of the long time it takes to reach a steady state, you might want to give Prozac (fluoxetine hydrochloride) a full two months.

8.  How to Stop Taking Prozac

Your doctor should be recommending that you reduce your dosage by 10–20mg a day every 3–4 four days, if not more slowly than that.

Now, if you’re one of the rare people who start to experience SSRI discontinuation syndrome then you will have to look at reducing your dosage by 10mg a day every week. If you’re prone to the worst effects of discontinuation syndrome be prepared for a longer time. It is highly unusual for anyone on Prozac to experience severe symptoms of SSRI discontinuation syndrome, but it has happened. Here’s where you really have to balance the suckiness of what you’re dealing with in the way of side effects or whatever is forcing you to stop vs. SSRI discontinuation syndrome, because you’re looking at reducing your dosage by 10mg a day every month. 
If you’re taking Prozac Weekly you’ll have to switch to the regular flavor to step down, as weekly is one size fits all. However, that extra-long half-life tends to make discontinuation less harsh, so you’ll probably be able to to get off of Prozac (fluoxetine hydrochloride) a lot sooner. In fact switching to Prozac (fluoxetine hydrochloride) from another SSRI or Effexor (venlafaxine) is a good way of dealing with the discontinuation syndrome of the meds with the shorter half-lives. As Prozac comes in a liquid form, you can always switch to that to wean yourself off the last bit really slowly, ml by ml.

9.  Prozac (fluoxetine HCl) Half-Life & Average Time to Clear Out of Your System

At 9.3 days (224 hours)3 Prozac’s active metabolite (norfluoxetine) has the longest half-life of any non-injected medication I’ve written up4. Fluoxetine itself has a half-life of 1 to 4 days (24 – 96 hours). That’s why there’s such an animal as Prozac Weekly. By Julien’s formula (see below) it takes 45 days to fully clear out of your system. I managed to find some numbers on how long it takes for Prozac to leave your brain, but as it is based on a sample of two people, it’s probably about as accurate as most of the PK data published across teh intergoogles:

The brain tissue fluoxetine half-life of 382 ± 48 hours (n = 2) was found to be close its plasma half-life of 406 ± 172 hours (ratio of half-lives = 1.0 ± 0.3) with only two subjects being studied for their tissue kinetics. —Brain Pharmacokinetics and Tissue Distribution In Vivo of Fluvoxamine and Fluoxetine by Fluorine Magnetic Resonance Spectroscopy

It’s because of fluoxetine’s & norfluoxetine’s long-ass half-lives that:

  • Prozac is the best antidepressant to give to anyone under 25, over 60, or who otherwise might not be very good about taking their meds consistently.
  • SSRI/SNRI discontinuation syndrome is so rare with Prozac that it is used to wean people off of SNRIs and other SSRIs if they are having too much trouble with withdrawing from their meds.

Half-life is the average time it takes for you to process half of the drug’s active ingredient. If a drug has a half-life of around 24 hours and you take a dose of 100mg, you’ll have roughly the equivalent a 50mg dose after one day, a 25mg dose after two days, and so on. The rule of thumb is: multiply the half-life by five and you get how long it is for the dose you took to be cleared from your bloodstream5, so there’s nothing swimming around to attach itself to your brain and start doing stuff. That’s called “plasma clearance.” Complete clearance is a complex equation based on a lot of factors which may or may not: be published in the PI sheet, include personal data like your weight, or even completely figured out by corporate and independent researchers. It usually winds up being 2–5 days after plasma clearance no matter what6, but can take weeks. Sometimes a drug will clear from your brain and other organs before it clears from your blood.

10.  Days to Reach a Steady State

Three to five weeks.

Steady state is the flipside of half-life. This is when you can expect to get over side effects caused by fluctuating amounts of a medication in your bloodstream. Often, but not always the same amount of time as the plasma clearance above.

11.  Prozac (fluoxetine HCl) Shelf life

Tablets: 3 years. Oral solution: 2 years.

12.  Other brand names & branded generic names1

  • Adofen (Spain)
  • Alzac 20 (Guatemala)
  • Andep (India)
  • Ansilan (Colombia)
  • Auroken (Mexico)
  • Deprexin (Bahamas; Barbados; Belize; Bermuda; Curacao; Guyana; Jamaica; Dutch Antilles; Puerto Rico; Singapore; Surinam; Trinidad)
  • Deproxin (Thailand)
  • Fluctin (Germany)
  • Fluctine (Austria; Switzerland)
  • Fludac (Benin; Burkina Faso; Ethiopia; Gambia; Ghana; Guinea; India; Ivory Coast; Kenya; Kuwait; Liberia; Libya Lebanon; Malawi; Mali; Mauritania; Mauritius; Morocco; Niger; Nigeria; Oman; Qatar; Republic of Yemen; Saudi Arabia; Senegal; Seychelles; Sierra Leone; South Africa; Sudan; Syria; Tanzania; Tunisia; Uganda; United Arab Emirates; Zambia; Zimbabwe)
  • Flufran (India)
  • Flunil (India)
  • Fluox (Germany)
  • Fluoxac (Mexico)
  • Fluoxeren (Italy)
  • Fluoxil (Dominican Republic)
  • Fluox-Puren (Germany)
  • Fluronin (Taiwan)
  • Flusac (Thailand)
  • Flutin (Colombia; Korea)
  • Flutine (Israel; Thailand)
  • Fluxen (Taiwan)
  • Fluxetil (Singapore)
  • Fluxetin (Singapore)
  • Fluxil (Bahrain; Cyprus; Egypt; Hong Kong; Iran; Iraq; Israel; Jordan; Kuwait; Lebanon; Libya; Oman; Qatar; Republic of Yemen; Saudi Arabia; Syria; United Arab Emirates)
  • Fontex (Denmark; Finland; Norway; Sweden)
  • Foxetin (Korea)
  • Lanclic (Korea)
  • Lorien (South Africa)
  • Lovan (Australia)
  • Magrilan (Singapore)
  • Margrilan (Bahrain; Cyprus; Egypt; Hong Kong; Iran; Iraq; Jordan; Kuwait; Lebanon; Libya; Oman; Qatar; Republic of Yemen; Saudi Arabia; Syria; Thailand; United Arab Emirates)
  • Modipran (Benin; Burkina Faso; Ethiopia; Gambia; Ghana; Guinea; Ivory Coast; Kenya; Kuwait; Liberia; Libya Lebanon; Malawi; Mali; Mauritania; Mauritius; Morocco; Niger; Nigeria; Oman; Qatar; Republic of Yemen; Saudi Arabia; Senegal; Seychelles; Sierra Leone; Sudan; Syria; Tanzania; Tunisia; Uganda; United Arab Emirates; Zambia; Zimbabwe)
  • Neupax (Peru)
  • Nopres (Indonesia)
  • Nuzak (South Africa)
  • Oxactin (United Kingdom)
  • Oxedep (China; India)
  • Pragmaten (Ecuador)
  • Prizma (Israel)
  • Proctin (Korea)
  • Prodep (Benin; Burkina Faso; Ethiopia; Gambia; Ghana; Guinea; India; Ivory Coast; Kenya; Kuwait; Liberia; Libya Lebanon; Malawi; Mali; Mauritania; Mauritius; Morocco; Niger; Nigeria; Oman; Qatar; Republic of Yemen; Saudi Arabia; Senegal; Seychelles; Sierra Leone; South Africa; Sudan; Syria; Tanzania; Tunisia; Uganda; United Arab Emirates; Zambia; Zimbabwe)
  • Rowexetina (Costa Rica; Dominican Republic; El Salvador; Guatemala; Honduras; Nicaragua; Panama)
  • Salipax (Bahamas; Barbados; Belize; Bermuda; Curacao; Guyana; Jamaica; Dutch Antilles; Puerto Rico; Surinam; Trinidad)
  • Sanzur (South Africa)
  • U-Zet (Taiwan)
  • ZAC (Indonesia)
  • Zactin (Australia; Singapore; Taiwan)
  • Zepax (Colombia)
  • Флуоксетин / Fluoxetine (Russia)

13.3  Full US PI sheet, Global SPCs & PILs, Other Consumer Review & Rating Sites, check for drug-drug interactions

Prozac’s Full US Prescribing Information / PI Sheet

UK Prozac SPC

Drugs.com’s drug-drug and drug-food interaction checker

It’s always a good idea to check for drug-drug interactions yourself. Just because most people in the crazy meds business know about really important interactions (e.g. MAOIs and a lot of stuff, warfarin and everything on the planet) doesn’t mean the person who prescribed your meds told you about them, or the pharmacist has all the meds you take at their fingertips like they’re supposed to. Or they have the time to do their jobs properly when not dealing with complete idiotsor playing Angry Farmers on the Faecesbooks.

14.  References

  1. Prozac (fluoxetine) Full US Prescribing Information

PDR: Physicians’ Desk Reference

Instant Psychopharmacology 2nd Edition Ronald J. Diamond M.D. © 2002. Published by W.W. Norton

Primer of Drug Action 12th edition by Robert M. Julien Ph.D, Claire D. Advokat, Joseph Comaty © 2011 Published by Worth Publishers

The Complete Guide to Psychiatric Drugs Edward Drummond, MD © 2000. Published by John Wiley & Sons, Inc.

Healing Anxiety & Depression Daniel G. Amen, M.D., and Lisa C. Routh, M.D. © 2003. Published by G.P. Putnam’s Sons.

Mosby’s Drug Consult (Generic Prescription Physician’s Reference Book Series)

Brain Pharmacokinetics and Tissue Distribution In Vivo of Fluvoxamine and Fluoxetine by Fluorine Magnetic Resonance Spectroscopy

T-Type Calcium Channels Are Inhibited by Fluoxetine and Its Metabolite Norfluoxetine

Multiple-Dose Pharmacokinetics of Fluoxetine in Healthy Mexican Subjects1 The term “branded generic” has three meanings:
1) A generic drug produced by a generics manufacturer that is a wholly-owned subsidiary of the company that makes the branded version. E.g. Greenstone Pharmaceuticals makes gabapentin, and they are owned by Pfizer, who also own Parke-Davis, the makers of Neurontin.
2) A branded generic is also a generic drug given a ‘brand’ name by the manufacturer (e.g. Teva’s Budeprion), but otherwise has the same active ingredient as the original branded version (Wellbutrin).
3) A branded generic is also a generic drug given a ‘brand’ name by the manufacturer (e.g. Sanofi-Aventis’ Aplenzin, which is bupropion hydrobromide) and uses a salt of the active ingredient that is different from the original branded version and other generics (Wellbutrin, Budeprion and all the others are bupropion hydrochloride). We aren’t sure if that really makes a difference or not. The FDA says they’re the same thing. As usual, the data are contradictory, but most evidence indicates that the FDA is right and the differences are negligible.
For our purposes a “branded generic name” refers to the second and third definitions.

2 If you’re taking Prozac for bulimia and you just spenched the capsule you normally take, having some of the mint-flavored oral solution around might be a really good idea.

3 And that’s just the average. The range is 7 to 15 days (168 to 360 hours). You could saw off a limb with a Swiss Army knife in that amount of time.

4 Is a tough call as to who has the longer half-life. ZyprexaRelprevv has a fairly consistent average of 30 days. InvegaSustenna’s is 25 days – 49 days. Some of the older antipsychotics may have longer ones.

5 Based on Julien’s calculations from A Primer of Drug Action, the half-life multiplied by five is the generally accepted estimate of how long it takes a single dose of any given drug to be eliminated from the blood stream/plasma of someone with a normal metabolism. That’s also the rough estimate for steady stage if they can’t get, or won’t provide a number for that.

6 For crazy meds. I have no idea what the average complete clearance is for other types of medications. For all I know there are drugs that utterly vanish from your system in under five passes, and others that won’t let go of your squishy bits for years after you stop taking them.

7 Thank you! I’ll be here all weak. Be sure to tip your content provider. And don’t try the veal, it’s cruelicious!