20 to 50     : Dose as in normal renal function
10 to 20     : Dose as in normal renal function
<10           : Start with small doses, i.e. 6.25 mg IM or 5 mg orally
DOSE IN PATIENTS UNDERGOING RENAL REPLACEMENT THERAPIES
CAPD                :Unlikely to be dialysed. Dose as in GFR <10 mL/min
HD                     :Unlikely to be dialysed. Dose as in GFR <10 mL/min
HDF/high flux   :Unknown dialysability. Dose as in GFR <10 mL/min
CAV/VVHD      :Unlikely to be dialysed. Dose as in normal renal function
IMPORTANT DRUG INTERACTIONS
Potentially hazardous interactions with other drugs
Anaesthetics: enhanced hypotensive effect
Analgesics: increased risk of convulsions with tramadol; enhanced hypotensive and sedative effects with opioidsAnti-arrhythmics increased risk of ventricular arrhythmias with anti-arrhythmics that prolong the QT interval, e.g. procainamide, disopyramide and amiodarone – avoid concomitant use with amiodarone
Antibacterials: increased risk of ventricular arrhythmias with moxifloxacin – avoid concomitant use
Antidepressants: increase concentrations and additive antimuscarinic effects, notably with tricyclics
Antimalarials: avoid concomitant use with artemether/lumefantrine
Antipsychotics: increased risk of ventricular arrhythmias with pimozide – avoid concomitant use
Antivirals: concentration possibly increased with ritonavirAnxiolytics and hypnotics: increased sedative effects
Atomoxetine: increased risk of ventricular arrhythmias
Beta-blockers: enhanced hypotensive effect; increased risk of ventricular arrhythmias with sotalolDesferrioxamine: avoid concomitant use
Diuretics: enhanced hypotensive effect
Lithium: increased risk of extrapyramidal side effects and possibly neurotoxicity
Pentamidine: increased risk of ventricular arrhythmias
Sibutramine: increased risk of CNS toxicity – avoid concomitant use
ADMINISTRATION
Reconstition
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Route
IM, IV (unlicensed), oral, buccal
Rate of Administration
IM or IV over 3–4 minutes
Comments
Unlicensed IV administration methods: Either: dilute with water for injection —to 5 times its own volume, and administer slowly over not less than 5 minutes,Or dilute to 1 mg/mL and administer at —rate not greater than 1 mg/minute
OTHER INFORMATION
Increased CNS sensitivity in severe renal impairment.