Fluoxetine (Oral Route)

Drug Information provided by: Micromedex

ARTICLE SECTIONS

US Brand Names

Prozac
Prozac Weekly
Rapiflux
Sarafem
Selfemra

Canadian Brand Names

Phl-Fluoxetine

Description

Fluoxetine is used to treat mental depression. It is also used to treat obsessive-compulsive disorder, bulimia nervosa, premenstrual dysphoric disorder (PMDD), and panic disorder .

Fluoxetine also may be used for other conditions as determined by your doctor.

Fluoxetine belongs to a group of medicines known as selective serotonin reuptake inhibitors (SSRIs). These medicines are thought to work by increasing the activity of a chemical called serotonin in the brain.

This medicine is available only with your doctor's prescription.

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in product labeling, fluoxetine is used in certain patients with the following medical conditions:

Premature ejaculation

This product is available in the following dosage forms:

Syrup
Capsule, Delayed Release
Tablet
Solution
Capsule

Before Using

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

This medicine has been tested in a limited number of children 7 to 18 years of age. These studies indicate that fluoxetine may help to treat depression and obsessive-compulsive disorder in children. However, unusual excitement, restlessness, irritability, and trouble in sleeping may be especially likely to occur in children, who seem to be more sensitive than adults to the effects of fluoxetine. Fluoxetine must be used with caution in children, teenagers, and young adults with depression. Studies have shown occurrences of children, teenagers, and young adults thinking about suicide or attempting suicide in clinical trials for this medicine. More study is needed to be sure fluoxetine is safe and effective in children, teenagers, and young adults .

Geriatric

Appropriate studies performed to date have not demonstrated geriatrics-specific problems that would limit the usefulness of fluoxetine in the elderly. However, elderly patients may be more sensitive to the effects of this medicine than younger adults, which may require caution in patients receiving fluoxetine.

Pregnancy

	Pregnancy Category	Explanation
All Trimesters	C	Animal studies have shown an adverse effect and there are no adequate studies in pregnant women OR no animal studies have been conducted and there are no adequate studies in pregnant women.

Breastfeeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Drug Interactions

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

Bepridil
Clorgyline
Dihydroergotamine
Ergoloid Mesylates
Ergonovine
Ergotamine
Furazolidone
Iproniazid
Isocarboxazid
Levomethadyl
Linezolid
Mesoridazine
Methylergonovine
Methysergide
Moclobemide
Nialamide
Pargyline
Phenelzine
Pimozide
Procarbazine
Selegiline
Terfenadine
Thioridazine
Toloxatone
Tranylcypromine

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

Bipolar disorder (mood disorder with alternating episodes of mania and depression) or risk of—May make condition worse. Your doctor will check you for this condition.

Brain disease or mental retardation or
Seizures, history of—The chance of having seizures may be increased.

Diabetes—The amount of insulin or oral antidiabetic medicine that you need to take may change.

Diseases that affect your body's metabolism—Caution should be used.

Kidney disease or
Liver disease—Higher blood levels of fluoxetine may occur, increasing the chance of side effects.

Parkinson's disease—May become worse.

Weight loss—Fluoxetine may cause weight loss. This weight loss is usually small, but if a large weight loss occurs, it may be harmful in some patients.

Proper Use

Take this medicine only as directed by your doctor, to benefit your condition as much as possible. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

If this medicine upsets your stomach, it may be taken with food.

If you are taking fluoxetine for depression, it may take 4 weeks or longer before you begin to feel better. Also, you may need to keep taking this medicine for 6 months or longer to stop the depression from returning. If you are taking fluoxetine for obsessive-compulsive disorder, it may take 5 weeks or longer before you begin to get better. Your doctor should check your progress at regular visits during this time.

If you are taking fluoxetine for bulimia nervosa, you may begin to get better after 1 week. However, it may take 4 weeks or longer before you get better.

If you are taking the oral liquid form of fluoxetine, shake the bottle well before measuring each dose. Use a small measuring cup or a measuring spoon to measure each dose. The teaspoons and tablespoons that are used for serving and eating food do not measure exact amounts .

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

For oral dosage forms (capsules or solution):
- For depression:
  - Adults—At first, usually 20 milligrams (mg) a day, taken as a single dose in the morning. Your doctor may increase the dose if needed. However, the dose usually is not more than 80 mg a day. Once your depression is under control, your doctor may wish to change you to a weekly dose. In this case, you will usually take a 90-mg capsule as a single dose one day per week.
  - Children above 8 years of age—At first, usually 10 or 20 milligrams (mg) a day, taken as a single dose in the morning. Your doctor may increase the dose if needed.
  - Children below 8 years of age—Use and dose must be determined by your doctor .
- For bulimia nervosa:
  - Adults—Usually 60 milligrams (mg) a day, taken as a single dose in the morning. Your doctor may start with a lower dose and increase it gradually. The dose usually is not more than 80 mg a day.
  - Children—Use and dose must be determined by your doctor.
- For obsessive-compulsive disorder:
  - Adults—At first, usually 20 milligrams (mg) a day, taken as a single dose in the morning. Your doctor may increase the dose if needed. However, the dose usually is not more than 80 mg a day.
  - Children above 7 years of age—At first, usually 10 milligrams (mg) a day, taken as a single dose in the morning. Your doctor may increase the dose if needed. However, the dose usually is not more than 60 mg a day.
  - Children below 7 years of age—Use and dose must be determined by your doctor .
- For panic disorder:
  - Adults—At first, 10 milligrams (mg) a day, taken as a single dose in the morning or evening for one week. Your doctor may increase your dose if needed. However, the dose is usually not more than 60 mg per day
  - Children—Use and dose must be determined by your doctor .
- For premenstrual dysphoric disorder:
  - Adults—At first, usually 20 milligrams (mg) a day, taken as a single dose in the morning. Your doctor may have you take 20 mg every day of your menstrual cycle or for only 14 days out of your cycle. Your doctor will determine the use and dose that is right for you. Your doctor may increase the dose if needed. However, the dose usually is not more than 80 mg a day.
  - Children—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions

It is important that your doctor check your progress at regular visits, to allow dosage adjustments and help reduce any side effects.

If you develop a skin rash or hives, stop taking fluoxetine and check with your doctor as soon as possible.

Fluoxetine may cause some people to be agitated, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. If you, your child, or your caregiver notice any of these unwanted effects, tell your doctor or your child's doctor right away .

Do not suddenly stop taking your fluoxetine. If you have been instructed to stop taking fluoxetine, ask your doctor how to slowly decrease the dose. This is to decrease the chance of having symptoms such as agitation, breathing problems, chest pain, confusion, diarrhea, dizziness or light-headedness, fast heartbeat, headache, increased sweating, muscle pain, nausea, restlessness, runny nose, trouble in sleeping, trembling or shaking, unusual tiredness or weakness, vision changes, or vomiting.

Do not take fluoxetine within 2 weeks of taking a monoamine oxidase (MAO) inhibitor activity (isocarboxazid [e.g., Marplan], phenelzine [e.g., Nardil], selegiline [e.g., Eldepryl], tranylcypromine [e.g., Parnate]) and do not take an MAO inhibitor for at least 5 weeks after taking fluoxetine. If you do, you may develop extremely high blood pressure or seizures.

Do not take thioridazine (e.g., Mellaril) while you are taking fluoxetine or less than 5 weeks after you have stopped taking fluoxetine. Using these medicines together can cause very serious heart problems.

Make sure your doctor knows about all the other medicines you are using. Fluoxetine may cause a serious condition called Serotonin Syndrome when taken with certain medicines such as linezolid [e.g., Zyvox], lithium, tryptophan, St. John's Wort, or some pain medicines (e.g., tramadol [e.g., Ultram], sumatriptan [e.g., Imitrex], zolmitriptan [e.g., Zomig], or rizatriptan [e.g., Maxalt]). Check with your doctor first before taking any other medicines .

Avoid drinking alcohol while you are taking fluoxetine.

For diabetic patients:

This medicine may affect blood sugar levels. If you notice a change in the results of your blood or urine sugar tests or if you have any questions, check with your doctor.

This medicine may cause some people to become drowsy or less able to think clearly, or to have poor muscle control. Make sure you know how you react to fluoxetine before you drive, use machines, or do anything else that could be dangerous if you are not alert and well able to control your movements.

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

More common

Decreased sexual drive or ability
Inability to sit still
Restlessness
Skin rash, hives, or itching

Less common

Chills or fever
Joint or muscle pain

Rare

Breast enlargement or pain
Convulsions (seizures)
Fast or irregular heartbeat
Purple or red spots on skin
Symptoms of hypoglycemia (low blood sugar), including anxiety or nervousness, chills, cold sweats, confusion, cool pale skin, difficulty in concentration, drowsiness, excessive hunger, fast heartbeat, headache, shakiness or unsteady walk, or unusual tiredness or weakness
Symptoms of hyponatremia (low blood sodium), including confusion, convulsions (seizures), drowsiness, dryness of mouth, increased thirst, lack of energy
Symptoms of serotonin syndrome, including diarrhea, fever, increased sweating, mood or behavior changes, overactive reflexes, racing heartbeat, restlessness, shivering or shaking
Talking, feeling, and acting with excitement and activity you cannot control
Trouble in breathing
Unusual or incomplete body or facial movements
Unusual secretion of milk, in females

Incidence not known

Abdominal or stomach pain
Agitation
Back or leg pains
Bleeding gums
Blindness
Blistering, peeling, or loosening of skin
Bloating
Blood in urine or stools
Bloody, black, or tarry stools
Blue-yellow color blindness
Blurred vision
Changes in behavior
Chest pain or discomfort
Clay-colored stools
Coma
Constipation
Continuing vomiting
Cough/dry cough
Dark urine
Decreased urine output
Decreased vision
Depression
Difficulty breathing
Difficulty swallowing
Dizziness or lightheadedness
Eye pain
Fainting
Fast, pounding, or irregular heartbeat or pulse
Fatigue
General body swelling
High fever
High or low blood pressure
Hives or welts
Hives, itching, puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
Hostility
Increased hunger
Indigestion
Irregular or slow heart rate
Irritability
Itching
Joint or muscle pain
Large, hive-like swelling on face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
Lethargy
Light-colored stools
Loss of appetite
Loss of bladder control
Muscle twitching
Nausea
Nightmares
No blood pressure or pulse
Noisy breathing
Nosebleeds
Pain in ankles or knees
Painful, red lumps under the skin, mostly on the legs
Pains in stomach, side, or abdomen, possibly radiating to the back
Palpitations
Pinpoint red spots on skin
Pounding heartbeat
Rapid weight gain
Red or irritated eyes
Red skin lesions, often with a purple center
Redness, tenderness, itching, burning, or peeling of skin
Severe muscle stiffness
Shortness of breath
Skin rash
Slurred speech
Sore throat
Sores, ulcers, or white spots on lips or in mouth
Stopping of heart
Stupor
Sudden shortness of breath or troubled breathing
Sudden weakness in arms or legs
Sudden, severe chest pain
Swelling of face, ankles, or hands
Swollen or painful glands
Thoughts of killing oneself
Tightness in chest
Tiredness
Twitching, twisting, uncontrolled repetitive movements of tongue, lips, face, arms, or legs
Unconsciousness
Unpleasant breath odor
Unusual bleeding or bruising
Unusually pale skin
Use of extreme physical or emotional force
Vomiting of blood
Wheezing
Yellow eyes or skin

Symptoms of overdose

Agitation and restlessness
Convulsions (seizures)
Drowsiness
Fast heartbeat
Nausea and vomiting
Talking, feeling, and acting with excitement and activity you cannot control
Trembling or shaking

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Anxiety or nervousness
Decreased appetite
Diarrhea
Drowsiness
Headache
Increased sweating
Nausea
Tiredness or weakness
Trembling or shaking
Trouble in sleeping

Less common or rare

Abnormal dreams
Change in sense of taste
Changes in vision
Chest pain
Constipation
Dizziness or light-headedness
Dryness of mouth
Feeling of warmth or heat
Flushing or redness of skin, especially on face and neck
Frequent urination
Hair loss
Increased appetite
Increased sensitivity of skin to sunlight
Menstrual pain
Stomach cramps, gas, or pain
Vomiting
Weight loss
Yawning

Incidence not known

Cracks in the skin
Loss of heat from the body
Painful or prolonged erections of penis
Red, swollen skin
Scaly skin

After you stop using this medicine, it may still produce some side effects that need attention. During this period of time, check with your doctor immediately if you notice the following side effects:

Actions that are out of control
Agitation
Anxiety
Burning, crawling, itching, numbness, prickling, “pins and needles”, or tingling feeling
Crying
Depersonalization
Dizziness
Euphoria
Feeling of distress
Feeling that body or surroundings are turning
General feeling of discomfort or illness
Headache
Irritability
Mental depression
Mood or mental changes
Nervousness
Nausea
Paranoia
Quick to react or overreact emotionally
Rapidly changing moods
Sleeplessness
Sweating
Talking, feeling, and acting with excitement
Trouble sleeping
Unable to sleep
Unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness
Unusual tiredness or weakness
Vaginal bleeding