Fluoxetine Hydrochloride Drug Interactions
Also known as: Fluoxetine
Fluoxetine is an antidepressant medication used to help improve mood and reduce symptoms in conditions like major depression, obsessive-compulsive disorder (OCD), bulimia nervosa, and panic disorder. It works by helping to restore the balance of a natural substance in the brain called serotonin.Fluoxetine Hydrochloride has 4 documented drug interactions in our database, including 2 contraindicated, 1 major, 1 moderate, and 0 minor interactions.
2
Contraindicated
1
Major
1
Moderate
0
Minor
The co-administration of fluoxetine and phenelzine is absolutely contraindicated due to a high risk of developing serotonin syndrome, a potentially life-threatening condition. Symptoms can include mental status changes, autonomic instability, and neuromuscular abnormalities.
Mechanism
Fluoxetine increases serotonin levels by inhibiting its reuptake, while phenelzine, an MAOI, prevents the metabolic breakdown of serotonin. This synergistic effect leads to excessive serotonin accumulation in the central nervous system.
Clinical Management
Fluoxetine and phenelzine must not be used concurrently. A washout period is required when switching between these medications: at least 14 days after discontinuing phenelzine before starting fluoxetine, and at least 5 weeks after discontinuing fluoxetine before starting phenelzine.
The combination of fluoxetine and tranylcypromine is contraindicated due to a high risk of serotonin syndrome, a potentially life-threatening condition characterized by mental status changes, autonomic instability, and neuromuscular abnormalities. This interaction can lead to severe and fatal outcomes.
Mechanism
Fluoxetine inhibits the reuptake of serotonin, increasing its concentration in the synaptic cleft. Tranylcypromine, an irreversible MAO inhibitor, prevents the enzymatic breakdown of serotonin. The combined effect leads to excessive serotonergic activity in the central nervous system.
Clinical Management
This combination is strictly contraindicated. A washout period of at least 5 weeks is required after discontinuing fluoxetine before initiating tranylcypromine. Conversely, at least 2 weeks should pass after discontinuing tranylcypromine before starting fluoxetine.
Co-administration of sertraline and fluoxetine, both potent serotonin reuptake inhibitors, significantly increases the risk of Serotonin Syndrome. Patients may experience symptoms such as mental status changes, autonomic instability, neuromuscular abnormalities, and gastrointestinal symptoms.
Mechanism
Both sertraline and fluoxetine increase serotonin levels in the central nervous system by inhibiting serotonin reuptake. Combining these agents leads to an additive effect, resulting in excessive serotonergic activity.
Clinical Management
Concomitant use of sertraline and fluoxetine is generally not recommended due to the high risk of Serotonin Syndrome. If co-administration is deemed necessary, monitor patients closely for signs and symptoms of Serotonin Syndrome, and consider dose reductions or alternative therapies.
Concomitant use of oxycodone and fluoxetine can increase oxycodone plasma concentrations, potentially leading to enhanced opioid effects such as respiratory depression, sedation, and constipation. Conversely, fluoxetine may reduce the analgesic efficacy of oxycodone.
Mechanism
Fluoxetine is a potent inhibitor of CYP2D6, the enzyme responsible for converting oxycodone to its active metabolite oxymorphone. This inhibition leads to increased oxycodone levels and decreased oxymorphone levels, altering the overall opioid effect.
Clinical Management
Monitor patients closely for signs of increased opioid effects (e.g., sedation, respiratory depression) or reduced analgesia when these drugs are co-administered. Consider starting with lower oxycodone doses or adjusting existing doses, and be prepared to manage adverse events. An alternative opioid or antidepressant may be considered.
For complete prescribing information:
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