FluoxetineFluoxetine Hydrochloride

About Fluoxetine

Fluoxetine is presumed to work by blocking the reuptake of serotonin in the brain. Capsules, tablets and the oral solution are labeled for major depressive disorder in adults and children 8 to 18, OCD in adults and children 7 to 17, and bulimia nervosa and panic disorder in adults. Some generic 10 and 20 mg tablets carry the former Sarafem labeling instead: premenstrual dysphoric disorder (PMDD) in adults, at 20 mg a day, taken every day or from 14 days before an expected period through its first full day. Taken with olanzapine, fluoxetine is labeled for depressive episodes of bipolar I disorder in adults and children 10 to 17, and for treatment-resistant depression in adults; fluoxetine alone is not indicated for either. Adults with depression or OCD start at 20 mg each morning, up to 80 mg a day; children start at 10 or 20 mg for depression and 10 mg for OCD. Panic disorder starts at 10 mg for a week, then 20 mg, and bulimia is treated with 60 mg each morning. The 90 mg weekly capsule is for depression, started 7 days after the last daily 20 mg dose.

The boxed warning says antidepressants increased the risk of suicidal thoughts and behavior in children, adolescents and young adults in short-term studies, and that fluoxetine is not approved for children under 7; everyone taking it is watched for worsening mood, especially early on and after dose changes. It is not taken with pimozide or thioridazine, with an MAO inhibitor or within 14 days of stopping one, and it is not started in someone receiving linezolid or intravenous methylene blue. Other warnings cover serotonin syndrome, rash and allergic reactions, mania, seizures, appetite and weight changes, bleeding, angle-closure glaucoma, low sodium, anxiety and insomnia, QT prolongation and sexual dysfunction. Nausea, insomnia, sleepiness, anxiety, nervousness, weakness, tremor, sweating, loss of appetite, diarrhea, dry mouth and sexual side effects are among the most common.

Fluoxetine and its active breakdown product, norfluoxetine, have long elimination half-lives, so a dose change takes several weeks to be fully reflected in the blood. At least 5 weeks must pass after stopping fluoxetine before an MAO inhibitor or thioridazine is started, and the dose is still lowered gradually rather than stopped abruptly when possible. It is a potent inhibitor of the liver enzyme CYP2D6 and can raise levels of tricyclic antidepressants and some other medicines. Use in the month before delivery may raise the risk of postpartum hemorrhage. Symbyax, the olanzapine and fluoxetine capsule, is listed as discontinued but sold as a generic.

Taking Fluoxetine

How to take it

Capsules, tablets and liquid once a day in the morning, or twice a day (morning and noon) for higher doses, with or without food. Take the delayed-release capsule once a week and swallow it whole; do not cut, crush or chew it.

If you miss a dose

Take it as soon as you remember, unless it is almost time for the next dose; then skip the missed dose and carry on as usual. Do not take a double dose. The weekly capsule’s Medication Guide gives the same rule.

Storage

At room temperature in the original, tightly closed container, away from light, excess heat and moisture (not in a bathroom), and out of reach of children.

Interactions to know about

Not with pimozide, thioridazine or an MAO inhibitor, including linezolid and methylene blue; wait at least 5 weeks after stopping fluoxetine before starting an MAO inhibitor or thioridazine. Triptans, tricyclic antidepressants, fentanyl, tramadol, meperidine, methadone, lithium, buspirone, amphetamines, tryptophan and St. John’s wort raise the risk of serotonin syndrome, and aspirin, NSAIDs and warfarin add to bleeding risk. It can raise levels of tricyclic antidepressants, phenytoin, carbamazepine, haloperidol, clozapine and alprazolam, and other drugs that prolong the QT interval are used with caution.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Fluoxetine differs from pharmacy to pharmacy

Each pharmacy sets its own cash price for generic fluoxetine from what it paid its supplier plus its own dispensing fee and markup, so quotes for the same capsules can differ.

Capsules, tablets, solution and the weekly capsule are different products that are not swapped at the counter, so each quote is for the form and strength written; a 60 mg daily dose can be written as one tablet or as capsules, and the two are quoted separately.

Ways to pay less for Fluoxetine without insurance

• Ask whether fluoxetine capsules are on the pharmacy’s flat-price generic list, and compare more than one pharmacy.
• If tablets, the oral solution or the weekly capsule are prescribed, ask the prescriber whether daily capsules would suit you, and compare quotes for both.
• If an old prescription names Prozac or Sarafem and does not allow substitution, ask the prescriber for a new one for generic fluoxetine.
• Once your dose is stable, ask for a ninety-day supply.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Fluoxetine

1. 1.Is my prescription for capsules, tablets, liquid or the weekly capsule, and can they be swapped?
2. 2.Which of my medicines could interact with it, even weeks after I stop?
3. 3.Should I take my whole dose in the morning or split it between morning and noon?
4. 4.What should I do if I miss my weekly capsule?

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