ADMINISTRATION ROUTES:
PO
ALTERNATIVE NAMES:
Fluox, Prozac
ICU INDICATIONS:
- Depression
Note: it is rare for antidepressants to be commenced in patients in the ICU. Most ICU patients have ‘situational depression’ and the risks of medication often outweigh the benefits. (see WARNINGS)
PRESENTATION AND ADMINISTRATION:
PO:
Capsules:
Fluox 20 mg capsules (purple / light green), Prozac 20 mg capsules (green / cream)
Dispersible Tablets:
Fluox dispersible 20 mg tablets (white)
DOSAGE:
PO:
20 - 60 mg OD
DOSAGE IN RENAL FAILURE AND RENAL REPLACEMENT THERAPY:
Dose in renal impairment
| GFR (ml/min) | DOSE |
|---|---|
| <10 | dose as in normal renal function or on alternate days |
| 10-20 | dose as in normal renal function or on alternate days |
| >20-50 | dose as in normal renal function |
Dose in renal replacement therapy
| MODALITY | DOSE |
|---|---|
| CAPD | dose as in normal renal function or on alternate days |
| HD | dose as in normal renal function or on alternate days |
| CVVHDF | dose as in normal renal function or on alternate days |
DOSAGE IN PAEDIATRICS:
PO:
0.5 mg/kg (max 20 mg) OD
Increase to maximum of 1 mg/kg (max 40 mg) BD
CLINICAL PHARMACOLOGY:
Fluoxetine is a serotonin specific reuptake inhibitor antidepressant
CONTRAINDICATIONS:
- Hypersensitivity to fluoxetine or other SSRIs
WARNINGS:
Use in Patients With Concomitant Illness
Clinical experience with fluoxetine in patients with concomitant systemic illness is limited. Caution is advisable in using fluoxetine in patients with diseases or conditions that could affect metabolism or haemodynamic responses.
Suicidality
Patients with major depressive disorder (MDD), both adult and paediatric, may experience worsening of their depression and/or the emergence of suicidal ideation and behaviour (suicidality) or unusual changes in behaviour, whether or not they are taking antidepressant medications, and this risk may persist until significant remission occurs.
Hyponatraemia
Cases of hyponatraemia (some with serum sodium lower than 110 mmol/L) have been reported. The hyponatraemia appeared to be reversible when Prozac was discontinued. Although these cases were complex with varying possible aetiologies, some were possibly due to the syndrome of inappropriate antidiuretic hormone secretion (SIADH).
PRECAUTIONS:
General:
Anaphylactoid events, including bronchospasm, angioedema, laryngospasm, and urticaria alone and in combination, have been reported.
Pulmonary events, including inflammatory processes of varying histopathology and/or fibrosis, have been reported rarely. These events have occurred with dyspnoea as the only preceding symptom.
Published case reports have documented the occurrence of bleeding episodes in patients treated with psychotropic drugs that interfere with serotonin reuptake. Subsequent epidemiological studies, both of the case-control and cohort design, have demonstrated an association between use of psychotropic drugs that interfere with serotonin reuptake and the occurrence of upper gastrointestinal bleeding.
Laboratory Tests:
No tests in addition to routine ICU tests are required
Drug/Laboratory Test Interactions:
None noted
IMPORTANT DRUG INTERACTIONS IN ICU:
The combination of Tramadol and SSRIs should be used with caution due to the increased risk of serotonin syndrome with concomitant use.
Patients on stable doses of phenytoin and carbamazepine have developed elevated plasma anticonvulsant concentrations and clinical anticonvulsant toxicity following initiation of concomitant fluoxetine treatment.
ADVERSE REACTIONS:
Body as a Whole:
Flu syndrome
Cardiovascular System:
Vasodilatation
Digestive System:
Nausea, diarrhoea, anorexia, dry mouth, dyspepsia
Nervous System:
Insomnia, anxiety, nervousness, somnolence, tremor
Respiratory System:
Pharyngitis, sinusitis
Skin and Appendages:
Sweating, rash