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Medical Assessment of the Older Driver


Peggy P. Barco

, OTD, OTR/L, BSW, SCDCM, CDRS, FAOTA, Washington University Medical School;

David B. Carr

, MD, Washington University School of Medicine

Reviewed/Revised Apr 2022 | Modified Sep 2022

Medical assessment of the older driver includes a thorough review of medical conditions and/or drugs that can impair driving ability. Such medical conditions can be chronic disorders that impair important functional abilities needed for driving (eg, macular degeneration that decreases vision) or acute events that impair consciousness (eg, seizure, syncope).

Therapeutic drugs

Older adults are likely to have multiple comorbidities and may be taking several drugs. A significant number of drugs, typically those affecting the central nervous system (eg, causing confusion, sedation) can potentially impair driving. Many have been shown to impair driving performance during road tests or in driving simulators and have been associated with an increase in motor vehicle crash (MVC) risk. Despite these risks, many of these drugs should not be stopped abruptly and may need to be tapered. Obtaining input from the prescribing physician or pharmacist is important before stopping them.

Some drugs that have been shown to increase driving risk include

  • Antihistamines, benzodiazepines, opioids, anticholinergics, hypnotics, antihypertensives, and tricyclic antidepressants, which can cause drowsiness, hypotension, or arrhythmias

  • Antiparkinsonian dopamine agonists (eg, pramipexole, ropinirole), which can occasionally cause acute sleep attacks

  • Antiemetics (eg, prochlorperazine) and muscle relaxants (eg, cyclobenzaprine), which can alter sensory perception

  • Antiseizure drugs, which can cause sedation (alternatives may need to be considered)

When starting a new drug that could affect visual, physical, or cognitive function, patients should refrain from driving for several days (depending on the time required to reach a steady state) to be sure no adverse effects occur.


Cardiac disorders

The presence of a cardiac disorder may increase driving risk, particularly disorders that may impair consciousness or cause syncope (eg, arrhythmias Overview of Arrhythmias The normal heart beats in a regular, coordinated way because electrical impulses generated and spread by myocytes with unique electrical properties trigger a sequence of organized myocardial... read more Overview of Arrhythmias ). Patients who have had cardiac procedures (eg, coronary artery stents or bypass grafts, placement of internal defibrillator/pacemakers) or certain acute events (eg, unstable angina Unstable Angina Unstable angina results from acute obstruction of a coronary artery without myocardial infarction. Symptoms include chest discomfort with or without dyspnea, nausea, and diaphoresis. Diagnosis... read more , myocardial infarction Acute Myocardial Infarction (MI) Acute myocardial infarction is myocardial necrosis resulting from acute obstruction of a coronary artery. Symptoms include chest discomfort with or without dyspnea, nausea, and/or diaphoresis... read more Acute Myocardial Infarction (MI) ) need to refrain from driving for a brief time during recovery; the length of time depends on the procedure and the patient's clinical condition. Cardiac disorders can cause chronic cognitive impairment (eg, sedation, drowsy driving) or acute impairment in consciousness (eg, dizziness, syncope).

Patients with severe heart failure Heart Failure (HF) Heart failure (HF) is a syndrome of ventricular dysfunction. Left ventricular (LV) failure causes shortness of breath and fatigue, and right ventricular (RV) failure causes peripheral and abdominal... read more Heart Failure (HF) (eg, class IV heart failure, dyspnea at rest or while driving) should refrain from driving until they can be evaluated with on-road testing and have the approval of their clinicians.

Neurologic disorders

Neurologic disorders also increase driving risk. Specific disorders include

Alzheimer disease Alzheimer Disease Alzheimer disease causes progressive cognitive deterioration and is characterized by beta-amyloid deposits and neurofibrillary tangles in the cerebral cortex and subcortical gray matter. Diagnosis... read more or progressive dementing disorders will eventually impair key functional abilities, including those required for driving. Monitoring patients for new driving errors that can be attributed to changes in cognition or identifying significant impairments in psychometric tests Cognitive function Adequate visual, motor, and cognitive abilities are needed to drive safely and require functional assessment to identify deficits. Some of these assessments can be done by primary health care... read more may be useful in determining referrals for on-road evaluation and/or possibly driving cessation. The American Academy of Neurology has practice parameters on driving and dementia (1 Neurologic disorders reference Medical assessment of the older driver includes a thorough review of medical conditions and/or drugs that can impair driving ability. Such medical conditions can be chronic disorders that impair... read more ). Several states presently require physicians to report significant cognitive impairment to the state's Department of Motor Vehicles.

Many other neurologic disorders (eg, Parkinson disease, multiple sclerosis) cause disability and should be monitored by functional assessment and, when appropriate, an on-road evaluation.

Diabetes mellitus

Diabetes mellitus Diabetes Mellitus (DM) Diabetes mellitus is impaired insulin secretion and variable degrees of peripheral insulin resistance leading to hyperglycemia. Early symptoms are related to hyperglycemia and include polydipsia... read more poses a risk because patients may become hypoglycemic while driving. Patients who have had a recent hypoglycemic episode with unawareness should not drive for 3 months or until factors contributing to the episode (eg, diet, activity, timing and dose of insulin or antihyperglycemic drug) have been assessed and managed. Sensory changes in the extremities due to neuropathy, retinopathy, or both caused by diabetes can also impair driving ability.

Severe hyperglycemia is associated with cognitive impairment, and patients should not drive until their blood glucose and symptoms are under better control.

Sleep disorders

Sleep disorders, most notably obstructive sleep apnea syndrome Obstructive Sleep Apnea (OSA) Obstructive sleep apnea (OSA) consists of multiple episodes of partial or complete closure of the upper airway that occur during sleep and lead to breathing cessation (defined as a period of... read more , can cause drowsiness leading to MVCs, and patients should refrain from driving until they are adequately treated. Use of a continuous positive airway pressure (CPAP) device has been shown to improve performance in a driving simulator and reduce MVCs.

Neurologic disorders reference

  • 1. Iverson DJ, Gronseth GS, Reger MA, et al: Practice parameter: Evaluation and management of driving and dementia: Report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology 74(16):1316–1324, 2010. doi: 10.1212/WNL.0b013e3181da3b0f

More Information

The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

Drugs Mentioned In This Article

Drug Name Select Trade
Mirapex, Mirapex ER
Requip, Requip XL
Compazine, Compazine Rectal, Compazine Solution, Compazine Syrup, Compro
Amrix, Fexmid, Flexeril
Afrezza, Exubera
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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