Trazodone Safety in Older Adults (65+): Risks, Dosing, and Monitoring

Why Trazodone Is So Common in Geriatric Practice

Trazodone ranks among the most frequently prescribed medications for sleep in older adults, despite having no FDA approval for insomnia at any age. A 2005 review by Mendelson documented that trazodone had become the most commonly prescribed agent for insomnia in the United States, with off-label sleep use far exceeding its on-label depression indication [1]. That pattern persists two decades later, and the geriatric population accounts for a disproportionate share of these prescriptions.

The Appeal Over Benzodiazepines and Z-Drugs

The reason is partly one of avoidance. Benzodiazepines and Z-drugs (zolpidem, eszopiclone) carry explicit warnings in the American Geriatrics Society (AGS) Beers Criteria against routine use in older adults due to fall risk, cognitive impairment, and delirium. Prescribers often reach for trazodone as a perceived safer alternative. But "safer than a benzodiazepine" does not mean safe, and the evidence base supporting trazodone for geriatric insomnia remains thin.

What the Evidence Actually Shows

No large randomized controlled trial has evaluated trazodone for insomnia specifically in adults aged 65 and older. The prescribing pattern rests largely on extrapolation from younger adult data and clinical habit. A 2017 systematic review published in the Journal of Clinical Sleep Medicine found that trazodone's sleep-promoting benefits were modest, short-lived (diminishing after the first week in some trials), and offset by next-day sedation. For geriatric patients, who already face age-related changes in drug metabolism and increased sensitivity to sedating medications, this risk-benefit calculation demands careful scrutiny.

Pharmacokinetics Change After 65

The way an older body handles trazodone differs meaningfully from a 35-year-old's. These pharmacokinetic shifts directly affect safety.

Slower Metabolism and Higher Drug Levels

Trazodone undergoes hepatic metabolism primarily through CYP3A4, producing the active metabolite meta-chlorophenylpiperazine (mCPP). In adults over 65, reduced hepatic blood flow and lower CYP enzyme activity can increase trazodone's half-life from a typical 7 to 13 hours to the upper end of that range or beyond. Peak plasma concentrations may be 20% to 30% higher in older adults receiving the same dose as younger patients.

Renal Clearance and Active Metabolites

The metabolite mCPP is pharmacologically active and contributes to anxiety and nausea at higher concentrations. With age-related decline in glomerular filtration rate (GFR drops roughly 8 mL/min per decade after age 40), mCPP accumulation becomes more likely. Clinicians should note that a "normal" serum creatinine in a thin 80-year-old may mask a GFR of 45 mL/min. Estimated GFR, not creatinine alone, should guide dose decisions.

Volume of Distribution

Older adults typically have increased body fat and decreased total body water. Trazodone is moderately lipophilic, meaning it distributes into fat tissue and may have a prolonged duration of action. This contributes to morning-after grogginess, a clinically relevant problem that increases fall risk during the first hours after waking.

Orthostatic Hypotension: The Primary Safety Concern

Orthostatic hypotension is the single most important safety issue with trazodone in geriatric patients. It overshadows every other adverse effect in clinical significance.

Mechanism and Prevalence

Trazodone blocks alpha-1 adrenergic receptors, which reduces sympathetic vascular tone and impairs the body's ability to compensate for positional blood pressure changes. In younger adults, this effect is usually mild. In older adults, who already have reduced baroreceptor sensitivity, diminished autonomic function, and often take antihypertensives, the result can be a systolic drop of 20 mmHg or more upon standing.

Estimates vary, but observational data suggest that clinically significant orthostatic hypotension occurs in 15% to 20% of geriatric trazodone users, compared to 5% to 7% in younger adults.

Downstream Consequences

A blood pressure drop at 2 a.m. When a patient stands to use the bathroom creates a chain of events: dizziness, unsteadiness, a fall, and potentially a hip fracture. Hip fractures in adults over 65 carry a one-year mortality rate of approximately 21%. This is not a theoretical concern. The connection between nighttime sedative use, orthostatic hypotension, and hip fracture is well-documented across multiple drug classes.

Mitigation Strategies

Practical steps reduce this risk without necessarily stopping the medication:

• Measure orthostatic vital signs before starting trazodone and at each dose increase
• Instruct patients to sit at the edge of the bed for 60 seconds before standing at night
• Ensure nightlights and a clear path to the bathroom
• Review concurrent antihypertensives and consider dose reduction of those agents if adding trazodone
• Use the lowest effective dose (25 mg is often sufficient for sleep)

Falls and Fracture Risk

Falls represent the most consequential adverse outcome associated with trazodone use in older adults. The connection goes beyond orthostatic hypotension alone.

Sedation and Psychomotor Impairment

Trazodone's antagonism at histamine H1 receptors and serotonin 5-HT2A receptors produces sedation. This is the desired effect for insomnia. But residual sedation extending into morning hours impairs balance, reaction time, and cognitive processing. A meta-analysis of antidepressants and fall risk found that sedating antidepressants, including trazodone, increased fall risk by approximately 1.5- to 2-fold compared to non-use. That effect size is comparable to benzodiazepines in some analyses.

The Beers Criteria Position

The 2023 AGS Beers Criteria update does not place trazodone in the "avoid" category for older adults (unlike benzodiazepines), but it does flag the drug under medications that may exacerbate falls and syncope. This "use with caution" designation is often misinterpreted as an endorsement. It is not. It reflects the absence of strong evidence in either direction, combined with the plausible pharmacologic risk.

Concurrent Fall-Risk Medications

The average adult over 65 takes five or more medications. Adding trazodone to a regimen that already includes an antihypertensive, a diuretic, or another CNS-active drug compounds fall risk in ways that are difficult to predict from individual drug profiles. Clinicians should perform a comprehensive medication review before initiating trazodone, specifically flagging alpha-blockers (tamsulosin, doxazosin), other sedating medications, and drugs that lower the seizure threshold.

Drug Interactions That Matter Most in Older Adults

Polypharmacy is the norm, not the exception, in geriatric medicine. Trazodone's interaction profile becomes more dangerous in this context.

CYP3A4 Inhibitors

Strong CYP3A4 inhibitors (ketoconazole, itraconazole, clarithromycin, ritonavir, and grapefruit juice in large quantities) can increase trazodone plasma concentrations by 50% to 75%. In older adults already experiencing reduced metabolism, this combination can produce excessive sedation, prolonged QT interval, and symptomatic hypotension. The FDA label recommends dose reduction when trazodone is combined with a strong CYP3A4 inhibitor.

Serotonin Syndrome Risk

Trazodone is a serotonin antagonist and reuptake inhibitor (SARI). Combining it with SSRIs, SNRIs, tramadol, linezolid, or other serotonergic agents raises the risk of serotonin syndrome. Symptoms include agitation, tremor, clonus, hyperthermia, and in severe cases, seizures. Older adults may present atypically, with confusion or delirium as the dominant feature rather than classic hyperkinetic signs. When trazodone is used for sleep alongside an SSRI for depression, the combination is common but requires monitoring.

QT Prolongation and Cardiac Risk

Trazodone carries a dose-dependent risk of QT prolongation. In older adults who may already be taking QT-prolonging medications (fluoroquinolones, ondansetron, certain antiarrhythmics), the additive cardiac risk is real. A baseline ECG is reasonable before starting trazodone in any patient over 65 who takes two or more medications known to affect the QT interval. The CredibleMeds QT drug list classifies trazodone as having conditional risk of torsades de pointes.

Anticoagulant Interactions

Trazodone may increase the anticoagulant effect of warfarin through protein-binding displacement. For patients on warfarin, INR should be checked within 5 to 7 days of starting trazodone and after any dose change. Direct oral anticoagulants (DOACs) appear less affected, but vigilance for bleeding signs remains appropriate.

Hyponatremia: An Underrecognized Geriatric Risk

Trazodone, like SSRIs and SNRIs, can cause syndrome of inappropriate antidiuretic hormone secretion (SIADH), leading to hyponatremia. This risk is particularly important in adults over 65.

Why Older Adults Are More Vulnerable

Baseline sodium regulation deteriorates with age. Reduced renal concentrating ability, lower total body water, and frequent use of thiazide diuretics create a substrate for hyponatremia. Adding trazodone to this environment can push a borderline sodium level into clinically symptomatic territory. A large cohort study found that antidepressant-associated hyponatremia occurs most frequently in the first two weeks of treatment and disproportionately affects women over 70.

Monitoring Recommendations

Check serum sodium at baseline, again at 1 to 2 weeks after starting trazodone, and periodically thereafter (especially after dose changes). Symptoms of hyponatremia in older adults can be subtle: confusion, lethargy, unsteadiness, and nausea may be attributed to "old age" or the sedative itself rather than recognized as a metabolic emergency. Sodium below 130 mEq/L warrants reassessment of the medication.

Appropriate Dosing for Adults Over 65

Geriatric dosing of trazodone follows the principle of "start low, go slow, but get there."

Starting and Titrating

For insomnia, begin at 25 mg at bedtime. This is half the dose commonly used in younger adults. If ineffective after 3 to 5 nights, increase to 50 mg. Doses above 100 mg for insomnia in adults over 65 are rarely justified and substantially increase the risk of next-day sedation, orthostatic hypotension, and falls. The 2023 APA Practice Guidelines for insomnia recommend using the lowest effective dose of any sedating agent in older populations.

When the Indication Is Depression

Antidepressant doses of trazodone (150 to 300 mg daily) are substantially higher than sleep doses. In older adults, the titration to therapeutic antidepressant levels should occur over weeks rather than days, with orthostatic vital signs checked at each increase. Split dosing (e.g., 50 mg in the afternoon and 100 mg at bedtime) can reduce peak-level adverse effects compared to a single large bedtime dose.

Renal and Hepatic Impairment

No specific dose adjustment is mandated in the FDA label for renal impairment, but clinical judgment dictates caution. For patients with eGFR below 30 mL/min or moderate hepatic impairment (Child-Pugh B), the starting dose should remain at 25 mg with slower titration intervals of 7 to 14 days between increases.

Deprescribing Trazodone in Older Adults

Starting a medication is a decision. Continuing it indefinitely without reassessment is not. Deprescribing, the planned process of dose reduction or discontinuation, is an active clinical skill that applies directly to trazodone.

When to Consider Stopping

Reassess the need for trazodone every 90 days. Questions to ask: Has the original insomnia trigger resolved? Has the patient's sleep improved through behavioral interventions? Are new adverse effects (morning confusion, falls, low sodium) now present? The Canadian Deprescribing Network recommends a trial of discontinuation for any sedative-hypnotic that has been used for more than 4 weeks in an older adult, provided the patient is willing.

Tapering Protocol

Abrupt discontinuation of trazodone can cause rebound insomnia and, less commonly, a discontinuation syndrome with irritability, anxiety, and nausea. A reasonable taper schedule:

• Reduce by 25 mg every 1 to 2 weeks
• For patients on 25 mg, alternate-night dosing for 1 to 2 weeks before stopping
• Pair the taper with sleep hygiene reinforcement (consistent wake time, dark/cool bedroom, no screens in bed)
• If rebound insomnia occurs, hold at the current dose for an additional 2 weeks before resuming the taper

Alternatives After Discontinuation

Cognitive behavioral therapy for insomnia (CBT-I) remains the first-line treatment recommended by the AASM for chronic insomnia in all adults, including those over 65. CBT-I produces durable improvements in sleep onset latency and total sleep time without pharmacologic risk. Digital CBT-I programs have made access substantially easier for patients who cannot attend in-person sessions.

Monitoring Checklist for Prescribers

A practical monitoring framework for any geriatric patient on trazodone:

• Before starting: Orthostatic vital signs, serum sodium, eGFR, ECG (if on other QT-prolonging drugs), fall risk assessment, full medication reconciliation
• Week 1 to 2: Sodium recheck, phone or visit follow-up for sedation and dizziness
• Month 1: Orthostatic vitals, subjective sleep improvement assessment, adverse effect screen
• Every 90 days: Reassess indication, check sodium if on diuretics, perform fall risk re-screening, discuss deprescribing if appropriate

Patients taking trazodone at doses above 50 mg for sleep, or at antidepressant doses, should have an ECG repeated annually or after any significant dose increase, particularly if their QTc was borderline at baseline (men >440 ms, women >460 ms).