Psychotropic Dosing in the Medically Ill requires different prescribing principles and considerations compared to healthy individuals. Individuals with cardiac, central nervous system, respiratory, gastrointestinal, and renal impairments all have different dosing considerations.
Class | Suggestion |
---|---|
Tricyclic Antidepressants | • Avoid in patients with cardiac disease • Increase heart rate, cause postural hypotension, slow cardiac conduction and have class I anti-arrhythmic activity • Cardiotoxic in overdose |
SSRIs | • Fluoxetine: mild bradycardia in elderly with pre-existing arrhythmias • Citalopram: dose dependant QTc interval prolongation, avoid doses > 40mg • Escitalopram: similar profile, but thought to be less risky • Sertraline: drug of choice in post-MI depression[4] |
Other Antidepressants | • Venlafaxine, duloxetine, bupropion: may affect blood pressure or heart rate • Trazodone: reports of orthostatic hypotension, arrhythmias, QTc prolongation (unlikely)[5] • Mirtazapine: no significant effects post-MI • Mianserin: low cardiotoxicity |
Antipsychotics | • Congestive heart failure: avoid agents that cause postural hypotension (low potency, clozapine, quetiapine) • Increased risk of sudden cardiac death[6] • Highest risk of prolonging QTc: pimozide, thioridazine, droperidol, sertindole, ziprasidone, quetiapine, haloperidol • Lowest effect on QTc: aripiprazole, paliperidone, clozapine, olanzapine, risperidone, sulpiride • Clozapine: myocarditis, cardiomyopathy • Order an ECG in at risk patients |
Mood stabilizers | • Lithium: non-specific ECG changes, uncommon: sinus node dysfunction, AV block, QTc prolongation, decreased clearance in CHF • Valproic acid is safe • Carbamazepine: cardiotoxic, AV conduction disturbances • Lamotrigine: clinically insignificant PR prolongation |
Dementia medications | • Cholinesterase inhibitors have vagotonic effects, avoid in patients with bradycardia (HR<50), conduction abnormalities, and unexplained syncopal episodes • Memantine: rarely causes bradycardia |
Stimulants | • Increase heart rate and blood pressure • Methylphenidate and dextroamphetamine have no significant cardiovascular effects at low doses • Contraindicated: structural cardiac abnormalities, cardiomyopathy, coronary artery disease, cardiac rhythm abnormalities • Modafinil increases BP in non-cardiac patients • Atomoxetine increases heart rate, blood pressure in non-cardiac patients, avoid in cardiac patients |
Class | Suggestion |
---|---|
Antidepressants | Antidepressants are generally safe |
Antipsychotics | • Antipsychotics may cause extrapydramidal symptoms including laryngeal dystonia or tardive dyskinesia • Clozapine carries a risk for respiratory arrest or depression,[7] and allergic asthma[8] |
Benzodiazepines | • Benzodiazepines should be avoided or reduced as they are a respiratory depressant • Lorazepam, oxazepam, and temazepam are the agents of choice if they must be used in COPD • All benzodiazepines are a relative contraindication in sleep apnea[9] • Non-benzodiazepine hypnotics such as ramelteon or buspirone are safer |
Dementia medications | • Acetylcholinesterase inhibitors (donepezil, galantamine, rivastigmine) should be used with caution in individuals with COPD, as it may exacerbate COPD |
Class | Suggestion |
---|---|
Antidepressants | • Anticholinergic TCAs can exacerbate hepatic encephalopathy • Citalopram, paroxetine, sertraline, and fluoxetine have all been used safely in patients with hepatitis C • Hepatotoxicity is a rare side effect of many antidepressants • Duloxetine is hepatotoxic in patients with liver disease • Bupropion and trazodone should be reduced in dose.[10] • Monitor QTc |
Antipsychotics | • Haloperidol most commonly chosen agent • Sulpiride/amisulpiride are also safe options • Avoid chlorpromazine • Clozapine is contraindicated in active liver disease, progressive liver disease and hepatic failure • Avoid low potency antipsychotics • Hepatotoxicity from second-generation (atypical) antipsychotics is rare |
Mood Stabilizers | • Carbamazepine and valproate are relatively contraindicated • Gabapentin is generally safe as it is renally excreted • Lithium may require dosage adjustment because of fluid shifts associated with ascites • Lamotrigine dose should be reduced according to severity of hepatic impairment |
Benzodiazepines | • Lorazepam, oxazepam, and temazepam are metabolized by phase II conjugation and have short half lives with no active metabolites, thus they are preferred agents in patients with hepatic disease • However, all benzodiazepines should be avoided in patients at risk of developing hepatic encephalopathy |
Dementia medications | • Acetylcholinesterase inhibitors (donepezil, galantamine, rivastigmine) should be used with caution • Memantine is mainly renally eliminated so no dose reduction required |
Medication | Hepatic Dose Adjustment |
---|---|
Alprazolam, diazepam, clonazepam | 50% reduction |
Lorazepam, oxazepam, temazepam | No reduction needed, but avoid in hepatic encephalopathy |
Paroxetine, fluoxetine, fluvoxamine, sertraline | Lower starting and target dose |
Citalopram, escitalopram | No reduction or minimal reduction |
Bupropion | Reduced dose in Child-Pugh Class A (least severe liver disease) |
Venlafaxine | >50% reduction in moderate liver disease |
Desvenlafaxine | No reduction (renally excreted) |
Duloxetine | Health Canada and FDA warning for patient's with liver disease |
Levomilnacipran | No reduction |
Vortioxetine | No reduction |
Valproate | Reduced dose (monitor LFTs); contraindicated in severe liver disease |
Carbamazepine | Reduced dose |
Lamotrigine | Reduced dose |
Gabapentin | No reduction (renally excreted) |
Lithium | No reduction (renally excreted) |
Risperidone, quetiapine | Reduced dose |
Olanzapine, ziprasidone, aripiprazole | No reduction in mild-moderate liver disease |
Paliperidone | No reduction (renally excreted) |
Donepezil, galantamine, rivastigmine | Reduced dose and use with caution |
Memantine | No reduction (renally excreted) |
Medication | eGFR 30-60 mL/min | eGFR 15-30 mL/min | eGFR less than 15 mL/min | Dialysis (PD or HD) | Comments |
---|---|---|---|---|---|
Citalopram | No adjustment | No adjustment | No adjustment | No adjustment | • Risk of QTc prolongation (max 40 mg/day or 20 mg/day with strong CYP2C19 inhibitors*) • Half as potent as escitalopram, therefore NOT interchangeable |
Escitalopram | No adjustment | SD: 10 mg/day | SD: 10 mg/day | (HD: not removed) | • Risk of QTc prolongation • Twice as potent as citalopram, therefore NOT interchangeable |
Fluoxetine | No adjustment | No adjustment | No adjustment | No adjustment | • Risk of QTc prolongation |
Fluvoxamine | No adjustment | No adjustment | No adjustment | No adjustment | • Many potential drug interactions • Most nauseating/sedating SSRI |
Paroxetine | SD: 10 mg/day | SD: 10 mg/day | SD: 10 mg/day | SD: 10 mg/day | • Most anticholinergic activity (caution in elderly) • Has been used for pruritus |
Sertraline | No adjustment | SD: 50 mg/day | SD: 25 mg/day | SD: 25 mg/day | - |
Medication | eGFR 30-60 mL/min | eGFR 15-30 mL/min | eGFR less than 15 mL/min | Dialysis (PD or HD) | Comments |
---|---|---|---|---|---|
Desvenlafaxine | SD: 50 mg q2 days | SD: 50 mg q2 days | SD: 50 mg q2 days | SD: 50 mg q2 days | - |
Duloxetine | No adjustment | SD: 30 mg/day | SD: 30 mg/day | SD: 30 mg/day | • Also Rx-peripheral neuropathy |
Venlafaxine | No adjustment | 37.5-112.5 mg/day | 37.5-112.5 mg/day | 37.5-112.5 mg/day | • Possibly more N/V than SSRIs • Also Rx-peripheral neuropathy |
Medication | eGFR 30-60 mL/min | eGFR 15-30 mL/min | eGFR less than 15 mL/min | Dialysis (PD or HD) | Comments |
---|---|---|---|---|---|
Trazodone | No adjustment | No adjustment | SD: 150 mg/day | SD: 150 mg/day | • Good choice for concomitant insomnia (usual dose for this indication: 25-50 mg) |
Bupropion | Max: 150 mg/day | Max: 150 mg/day | Max: 150 mg/day | Max: 150 mg/day | • Risk of accumulation of toxic metabolites causing dysrhythmia (wide QRS complex) • Caution in seizure disorders |
Mirtazapine | No adjustment | 15 mg/day | 15 mg/day | 15 mg/day | • Also used for pruritus • Good choice for concomitant insomnia (dose: 7.5-15 mg HS) |
Class | Suggestion |
---|---|
Antidepressants | • Virtually all antidepressants can be used • SSRIs first line: sertraline, citalopram • TCAs: Nortriptyline is preferred • Reduce dose: venlafaxine, desvenlafaxine, bupropion, paroxetine, mirtazapine, and reboxetine |
Antipsychotics | • All antipsychotics can be used • First line: haloperidol 2-6mg, olanzapine 5mg (both undergo minimal renal excretion) • Reduce dose: risperidone and its metabolite paliperidone (9-hydroxyrisperidone) is renally excreted[12] • Avoid amisulpiride and sulpiride • Avoid highly anticholinergic agents |
Benzodiazepines and Z-Drugs | • Monitor for excessive sedation • Lorazepam, oxazepam, zopiclone are preferred agents • Dose reduction required in end stage renal disease (ESRD) • Avoid barbiturates, which can cause osteomalacia and sedation • Do not use diazepam due to its long half life |
Mood Stabilizers[13] | • Lithium is entirely excreted by kidneys, and thus contraindicated in acute renal failure but not chronic renal failure • Lithium completely is also dialysed, give single oral dose after dialysis, check levels 2-3 hours after dialysis • First line: valproate, carbamazepine, carbamazepine, start at a low dose and increase slowly |
Dementia medications | • Limited data, but donepezil is generally thought to be safest out of all acetylcholinesterase inhibitors in renal impairment.[14] • Rivastigmine can be used, but should be avoided in severe renal impairment. • Avoid galantamine in moderate to severe renal impairment • Reduce dose of memantine depending on severity of kidney impairment: – Severe impairment (creatinine clearance 5 to 29 mL/min) maximum dose 10mg daily. – Avoid if creatinine clearance less than 5ml/min |
Gabapentinoids | • Gabapentin and pregabalin are significantly renally excreted |
Stimulants | • No dose reduction required |
Drug | Effect on CYP2D6 | Advice |
---|---|---|
Venlafaxine | Minimal | Safest choice if taken with tamoxifen |
Desvenlafaxine, mirtazapine | Direct studies with tamoxifen are lacking, but effect on endoxifen levels should be minimal. | Also a reasonable choice |
Citalopram, escitalopram | Mild | Secondary choice if above are not options. Only citalopram and sertraline have been studied directly with tamoxifen, so risk of reducing levels of endoxifen should be weighed against benefits of antidepressants. |
Duloxetine, sertraline, fluvoxamine | Moderate | Weigh risks carefully |
Paroxetine, fluoxetine, bupropion | Strong | Avoid if taking tamoxifen |
Drug | Interaction |
---|---|
Desipramine, haloperidol, fluoxetine, fluvoxamine, sertraline, trazodone | Increases cyclosporine and tacrolimus levels, with potential to cause toxicity |