fluphenazine decanoate
fluphenazine hydrochloride
Pharmacologic class: Phenothiazine, dopaminergic blocker
Therapeutic class: Anxiolytic, antipsychotic
Pregnancy risk category C
Action
Unclear. May alter postsynaptic mesolimbic dopamine receptors in brain and reduce release of hypothalamic and hypophyseal hormones thought to depress reticular activating system, thereby preventing psychotic symptoms.
Availability
fluphenazine decanoate
Depot injection: 25 mg/ml
fluphenazine hydrochloride
Elixir: 2.5 mg/5 ml
Injection: 2.5 mg/ml
Oral concentrate: 5 mg/ml
Tablets: 1 mg, 2.5 mg, 5 mg, 10 mg
Indications and dosages
➣ Psychotic disorders
Adults: 2.5 to 10 mg/day (hydrochloride) P.O. in divided doses q 6 to 8 hours or as a single dose at bedtime; typical daily dosage is 1 to 5 mg; give oral doses above 20 mg/day with caution. Or initially, 1.25 mg I.M., divided and given q 6 to 8 hours. Parenteral hydrochloride dosage is one-third to one-half of oral dosage. Or 12.5 to 25 mg I.M. or subcutaneously (decanoate); base subsequent dosage and dosing intervals of 1 to 4 weeks on patient response; don't exceed 100 mg.
Dosage adjustment
• Elderly patients
Contraindications
• Hypersensitivity to drug, sulfites (with injectable form), or benzyl alcohol
• Angle-closure glaucoma
• Bone marrow depression
• Severe hepatic or cardiovascular disease
Precautions
Use cautiously in:
• diabetes, respiratory disease, prostatic hypertrophy, CNS tumors
• elderly patients
• pregnant or breastfeeding patients (safety not established)
• children with acute illnesses, infections, gastroenteritis, or dehydration.
Administration
☞ Be aware that parenteral form is for I.M. and subcutaneous use only. Don't give I.V.
• Don't give parenteral form to comatose or severely depressed patient.
• Use gloves when handling. To prevent contact dermatitis, keep drug away from clothing and skin.
• Dilute concentrated oral forms in juice, milk, or semisolid food just before administering.
• Give long-acting, oil-based preparations with dry needle of at least 21G.
• Be aware that antacids and adsorbent antidiarrheals may decrease adsorption of fluphenazine. Give 1 hour before or 2 hours after fluphenazine.
Adverse reactions
CNS: drowsiness, sedation, extrapyramidal reactions, tardive dyskinesia, pseudoparkinsonism, neuroleptic malignant syndrome, seizures
CV: hypotension, tachycardia
EENT: blurred vision, dry eyes, lens opacities, nasal congestion
GI: constipation, dry mouth, anorexia, paralytic ileus
GU: urinary retention, menstrual irregularities, inhibited ejaculation, priapism, gynecomastia, lactation
Hematologic: eosinophilia, hemolytic anemia, aplastic anemia, agranulocytosis, leukopenia, thrombocytopenia
Hepatic: jaundice, hepatitis
Metabolic: galactorrhea, hyperthermia
Skin: photosensitivity, rash
Other: allergic reactions, pain at injection site, sterile abscess
Interactions
Drug-drug. Activated charcoal, adsorbent antidiarrheals, antacids: decreased fluphenazine adsorption
Anticholinergics: decreased fluphenazine effects
Antidepressants, antihistamines, general anesthetics, MAO inhibitors, opioid analgesics, sedative-hypnotics: additive CNS depression
Antihistamines, disopyramide, quinidine, tricyclic antidepressants (TCAs): increased risk of anticholinergic effects
Antihypertensives: additive hypotension
Barbiturates: increased fluphenazine metabolism and decreased efficacy
Bromocriptine: decreased bromocriptine efficacy
Guanethidine: inhibition of antihypertensive effects
Lithium: disorientation, unconsciousness, extrapyramidal symptoms
Meperidine: excessive sedation and hypotension
Ofloxacin: increased QTc interval
Phenytoin: increased or decreased phenytoin blood level
Pimozide: increased risk of potentially serious cardiovascular reactions
Propranolol: increased blood levels of both drugs
TCAs: increased blood levels and effects of TCAs
Drug-diagnostic tests. Alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, bilirubin: increased levels
Granulocytes, hematocrit, hemoglobin, leukocytes, platelets: decreased values
Pregnancy tests: false-positive or false-negative result
Urine bilirubin: false-positive result
Drug-herbs. Angel's trumpet, jimsonweed, scopolia: increased anticholinergic effects
Chamomile, hops, kava, skullcap: increased CNS depression
St. John's wort: photosensitivity
Yohimbe: fluphenazine toxicity
Drug-behaviors. Alcohol use: increased CNS depression
Sun exposure: increased risk of photosensitivity
Patient monitoring
☞ Monitor patient for signs and symptoms of neuroleptic malignant syndrome (extrapyramidal symptoms, hyperthermia, autonomic symptoms).
☞ Stop giving drug and notify prescriber immediately if patient shows signs or symptoms of blood dyscrasias (fever, infection, sore throat, cellulitis, or weakness).
• Observe for tardive dyskinesia.
• Watch for bleeding tendency.
• Monitor CBC, bilirubin level, and liver function test results.
• Assess kidney function and ophthalmic test results in patients on long-term therapy.
Patient teaching
☞ Tell patient not to stop taking drug suddenly, because serious adverse effects may occur.
• Advise patient to report urinary retention or constipation.
☞ Instruct patient to immediately report unusual bleeding or bruising.
• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration, alertness, and vision.
• Tell patient to avoid activities that can cause injury. Advise him to use soft toothbrush and electric razor to avoid gum and skin injury.
• Inform patient that he'll undergo regular blood testing during therapy.
• Tell female patient to inform prescriber if she is pregnant or breastfeeding.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, herbs, and behaviors mentioned above.