Compare Prozac vs. Effexor

Head-to-head comparisons of medication uses, side effects, ratings, and more.

Prozac
(Fluoxetine)

Effexor
(Venlafaxine)

Improves mood and helps you relax. Prozac (Fluoxetine) is good for treating depression and anxiety. It's more energizing than other antidepressants, but may not be the best choice for people who have trouble sleeping.Improves mood and helps you relax. Effexor (Venlafaxine) is good for treating depression and anxiety. May work when other antidepressants haven't, it's but more likely to cause side effects and withdrawal symptoms than other antidepressants.
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Reviews & ratings
Button Group. All currently active
Button Group. All currently active
4.7375Prozac
Reviews for Prozac (Fluoxetine)
61%
of people say Prozac (Fluoxetine) is worth it
40%
say it works well
16%
say it's a big hassle
Reviews for Effexor (Venlafaxine)
61%
Same vs. Prozac (Fluoxetine)
50%
+10% vs. Prozac (Fluoxetine)
22%
6% vs. Prozac (Fluoxetine)
Side effects
ProzacEffexor
  • Rash 57%
  • Sleep difficulty 20%
  • Nausea 18%
  • Muscle weakness 12%
  • Drowsiness 10%
  • Tremor 9%
  • Dry mouth 9%
  • Lower sex drive 9%
  • Loss of appetite 7%
  • Anxiety 7%
More Prozac side effects »
  • Nausea 42%
  • Drowsiness 22%
  • Dizziness 20%
  • Nervousness 17%
  • Sleep difficulty 16%
  • Loss of appetite 15%
  • Sweating 14%
  • Dry mouth 13%
  • Dry mouth 11%
  • Muscle weakness 10%
More Effexor side effects »
How it works
ProzacEffexor
Prozac (Fluoxetine) is a selective serotonin reuptake inhibitor (SSRI) antidepressant. It increases serotonin activity in the brain, which regulates mood.Effexor (Venlafaxine) is a serotonin and norepinephrine reuptake inhibitor (SNRI) antidepressant. It increases serotonin and norepinephrine activity in the brain, which regulate mood.
Type of medication
ProzacEffexor
Antidepressant
Selective serotonin reuptake inhibitor (SSRI)
Prescription only
Antidepressant
Serotonin-norepinephrine reuptake inhibitor (SNRI)
Prescription only
Available as
ProzacEffexor
  • Pill
  • Delayed release capsule
  • Liquid
  • Pill
  • Extended release
Used for (click to learn more)
ProzacEffexor
How well it works for depression
The free Iodine Start program helps people track how well they are improving, and find the right antidepressant faster.

After 4 weeks using Start and Prozac (Fluoxetine), here’s how much better people feel.

After 4 weeks using Start and Effexor (Venlafaxine), here’s how much better people feel.

Risk factors for serious side effects
ProzacEffexor
  • Age 24 years or younger
  • Using other medications that affect serotonin
  • Stopping Prozac (Fluoxetine) suddenly
  • History of heart problems
  • History of liver problems
  • Drug interactions
  • Taking other blood-thinning drugs
    • History of bipolar disorder
    • At risk for bipolar disorder
    Detailed Prozac (Fluoxetine) risks & warnings »
    • Age 24 years or younger
    • Using other medications that affect serotonin
    • Stopping Effexor (Venlafaxine) suddenly
    • History of high blood pressure
    • Taking other blood-thinning drugs
      • History of bipolar disorder
      • At risk for bipolar disorder
      Detailed Effexor (Venlafaxine) risks & warnings »
      Pregnancy category
      ProzacEffexor
      CFDA pregnancy category (Weigh risks vs. benefits)

      Research studies with animals found harmful effects on unborn babies. It hasn’t been properly studied in humans. The benefits might outweigh the risks even if you’re pregnant. Talk with your doctor.

      See the FDA package insert
      CFDA pregnancy category (Weigh risks vs. benefits)

      Research studies with animals found harmful effects on unborn babies. It hasn’t been properly studied in humans. The benefits might outweigh the risks even if you’re pregnant. Talk with your doctor.

      See the FDA package insert
      Alcohol
      No specific alcohol-related info.No specific alcohol-related info.
      Food
      • Take in the morning with food to avoid side effects.
      • You can take the extended-release form once a day with food either in the morning or in the evening at about the same time each day.
      Kidneys and liver
      No specific kidneys and liver-related info.No specific kidneys and liver-related info.
      Sex
      • Can cause sexual side effects like low libido and an inability to orgasm or ejaculate.
      • Prozac (Fluoxetine) can cause lower sex drive or difficulty having an orgasm. If the problem persists after the first 2 to 3 months, you can talk to your doctor about alternative antidepressants or performance-enhancing medications.
      • Can cause sexual side effects like low libido and an inability to orgasm or ejaculate.
      • Effexor (Venlafaxine) can cause lower sex drive or difficulty having an orgasm. If the problem persists after the first 2 to 3 months, you can talk to your doctor about alternative antidepressants or performance-enhancing medications.
      Sleep
      • Stopping Prozac (Fluoxetine) suddenly may cause withdrawal symptoms such as nausea, anxiety, agitation, flu-like symptoms, trouble sleeping, and dizziness. Withdrawal symptoms usually occur within 3 days of stopping the medication, and go away within 1 to 2 weeks. Work with your doctor to gradually reduce your dose.
      • Causes more sleepiness than other antidepressants, so it's good for people who have trouble sleeping.
      • Stopping Effexor (Venlafaxine) suddenly may cause withdrawal symptoms such as nausea, anxiety, agitation, flu-like symptoms, trouble sleeping, and dizziness. Withdrawal symptoms usually occur within 3 days of stopping the medication, and go away within 1 to 2 weeks. Work with your doctor to gradually reduce your dose.
      Weight
      No specific weight-related info.No specific weight-related info.
      Upsides and benefits
      ProzacEffexor
      • Lowers relapse rates of depression and bulimia nervosa.
      • Causes less sleepiness than other antidepressants.
      • It's more energizing than other antidepressants, so it's good for people who have low energy.
      • It has been used to treat depression for a long time, so there's a lot of information available about how it works and how safe it is.
      • Effective at relieving depression and anxiety symptoms.
      • Six out of ten people who use an antidepressant for the first time find that it works for them.
      • Lowers relapse rates of depression.
      • Causes more sleepiness than other antidepressants, so it's good for people who have trouble sleeping.
      • Might work when other antidepressants haven't worked since it affects two chemicals in the brain that impact your mood. Many other antidepressants affect only serotonin, but not norepinephrine too.
      • Effective at relieving depression and anxiety symptoms.
      • Six out of ten people who use an antidepressant for the first time find that it works for them.
      Downsides and risks
      ProzacEffexor
      • Can increase feelings of anxiety or cause headaches during the first few weeks of taking it. These effects should go away over time.
      • More likely than other antidepressants to interact with other medications you're taking.
      • Can cause sexual side effects like low libido and an inability to orgasm or ejaculate.
      • Like most antidepressants, it can cause a higher risk of suicidal thoughts and behavior for people younger than 24.
      • The first antidepressant you try doesn't always work or it can cause side effects you really don't like. You might need to try a few different medications until you find one that works for you.
      • Not the best option for people with high blood pressure.
      • Overdosing on this medication could be fatal.
      • It's more likely to cause nausea and vomiting or make you feel sick if you miss a dose than other antidepressants. Also causes more sleepiness than others.
      • Can cause sexual side effects like low libido and an inability to orgasm or ejaculate.
      • Like most antidepressants, it can cause a higher risk of suicidal thoughts and behavior for people younger than 24.
      • The first antidepressant you try doesn't always work or it can cause side effects you really don't like. You might need to try a few different medications until you find one that works for you.
      Tips from our pharmacists for people taking the medication
      ProzacEffexor
      • Take in the morning with food to avoid side effects.
      • Takes about 8 to 12 weeks to see the medication's full effects on your mood.
      • Stop taking it slowly to avoid getting withdrawal symptoms.
      • Tell your doctor if you notice sudden mood changes or unusual thoughts.
      • You can take the extended-release form once a day with food either in the morning or in the evening at about the same time each day.
      • Extended-release capsules should be swallowed whole. If you can’t swallow pills, open the capsule, sprinkle it on a spoonful of applesauce and then swallow it without chewing.
      • Takes about 8 to 12 weeks to see the medication's full effects on your mood.
      • Stop taking it slowly to avoid getting withdrawal symptoms.
      • Tell your doctor if you notice sudden mood changes or unusual thoughts.
      Learn more
      More about ProzacSide effectsReviews & ratingsAlternativesFDA package insert
      More about EffexorSide effectsReviews & ratingsAlternativesFDA package insert