2.4 Medication Effects, Polypharmacy & Occupational Performance
Key Takeaways
- COTAs never prescribe, adjust, administer, or withhold medication; the COTA's blueprint responsibility is to recognize how a client's medications alter occupational performance, adapt the session, and report observations to the supervising OTR and nursing.
- Polypharmacy is conventionally defined as the concurrent use of five or more medications, and the AGS Beers Criteria (2023 update) is the reference list of potentially inappropriate medications in adults 65 and older.
- Anticholinergic burden produces a recognizable functional cluster — dry mouth, blurred near vision, constipation, urinary retention, confusion, and impaired heat tolerance — that directly degrades reading, feeding, toileting, and community participation.
- Beta-blockers blunt the heart-rate response to exertion, so activity intensity must be graded with a rating of perceived exertion scale rather than a target heart rate.
- Session timing is a legitimate clinical intervention: schedule therapy at the analgesic peak, during a Parkinson's client's medication 'on' period, and away from the sedation window that follows a benzodiazepine or opioid dose.
Medication Effects, Polypharmacy & Occupational Performance
The COTA blueprint lists medication side effects and interactions among the internal and external factors that influence a client's engagement in occupation. That single line carries real weight: on any given caseload, the reason a client suddenly cannot complete a morning ADL routine is at least as likely to be pharmacological as it is musculoskeletal.
Be clear about the boundary before anything else. A COTA does not prescribe, adjust doses, administer, withhold, or counsel on the pharmacology of a medication. What the COTA does is recognize a functional change, connect it to a plausible medication-related cause, adapt the activity to keep the client safe, document objectively, and report to the supervising OTR and the nurse. On the exam, any option in which the COTA changes a medication, tells the client to skip a dose, or interprets a drug level is wrong on its face.
1. Polypharmacy & the AGS Beers Criteria
Polypharmacy is conventionally defined as the concurrent use of five or more medications. Each additional agent multiplies the chance of an interaction, and older adults are more sensitive to many drugs because of altered metabolism, reduced renal clearance, and changed body composition.
The American Geriatrics Society (AGS) Beers Criteria, most recently updated in 2023, is the standard explicit list of potentially inappropriate medications (PIMs) for adults aged 65 and older. It is organized into tables covering medications to avoid in most older adults, medications to avoid with specific conditions, medications to use with caution, clinically important drug–drug interactions, renal dosing, and — critically for occupational therapy — a dedicated table of drugs with strong anticholinergic properties. The 2023 update specifically strengthened the warnings about cumulative anticholinergic burden and about combining three or more CNS-active drugs.
PIM use is associated with falls, cognitive decline, frailty, hospitalization, and mortality — the exact outcomes occupational therapy is trying to prevent.
[!NOTE] The COTA does not perform a medication reconciliation and does not decide whether a drug is appropriate. Knowing that Beers-listed agents are a red flag lets the COTA raise the right question with the OTR and the nurse: "This client is on three sedating medications and just failed a transfer she passed yesterday — should the team review this?"
2. Drug Classes Mapped to Occupational Consequences
| Drug Class | Common Functional Effect | COTA Adaptation |
|---|---|---|
| Antihypertensives, diuretics, alpha-blockers | Orthostatic hypotension, dizziness on rising; diuretics add urinary urgency and frequency | Change position in stages with a seated pause; check blood pressure before standing ADLs; schedule toileting proactively and avoid scheduling a session at the peak diuretic window |
| Benzodiazepines, "Z-drugs," sedative-hypnotics | Sedation, slowed reaction time, impaired new learning, markedly increased fall risk (Beers-listed) | Avoid the 1–2 hours after dosing for high-demand mobility; reduce cognitive load; use errorless teaching; strict fall precautions |
| Opioid analgesics | Sedation, nausea, constipation, delirium risk; but also a window of improved tolerance for movement | Schedule demanding ROM or transfer work at the analgesic peak; screen for over-sedation before mobilizing; expect bowel-routine impact on toileting goals |
| Anticoagulants and antiplatelets (warfarin, DOACs) | Easy bruising, hematoma, prolonged bleeding from minor skin trauma | Avoid aggressive resistive work, forceful manual techniques, and high-fall-risk tasks when the INR is supratherapeutic; pad splints and equipment edges; inspect skin |
| Antipsychotics | Extrapyramidal effects — parkinsonian rigidity, akathisia, tardive dyskinesia — plus sedation and orthostasis | Report new tremor, restlessness, or involuntary orofacial movement immediately; adapt for reduced dexterity; expect impact on feeding and handwriting |
| Carbidopa–levodopa (Parkinson's disease) | "On/off" fluctuations, end-of-dose wearing off, peak-dose dyskinesia | Book the session during the "on" period (commonly beginning roughly 45–60 minutes after a dose); document performance in both states so the OTR and physician can see the pattern |
| Corticosteroids | Skin fragility and easy tearing, proximal muscle weakness, hyperglycemia, long-term bone loss | Use gentle handling and padded straps; monitor for proximal weakness in sit-to-stand; fall precautions for bone fragility |
| Beta-blockers | Blunted heart-rate rise with exertion, so heart rate under-reports true workload | Grade intensity with a rating of perceived exertion (RPE) scale and symptom monitoring rather than a target heart rate |
| Chemotherapeutic agents | Cancer-related fatigue, chemotherapy-induced peripheral neuropathy, neutropenia, nausea | Energy conservation and pacing; protective sensation training and thermal safety; follow neutropenic precautions |
| Anticholinergic agents (many antihistamines, bladder antispasmodics, tricyclics, some antipsychotics) | The classic cluster: dry mouth, blurred near vision, constipation, urinary retention, confusion, impaired sweating and heat tolerance | Enlarge print and increase task lighting; ensure hydration and oral care; watch for delirium; avoid hot environments and monitor for overheating |
The Anticholinergic Cluster Is an ADL Problem, Not Just a Symptom List
Take a single client on a bladder antispasmodic plus a sedating antihistamine plus a tricyclic. The blurred near vision blocks reading a medication label or a recipe. Dry mouth impairs bolus formation and makes swallowing thicker textures harder. Constipation disrupts the bowel program that the toileting goal depends on. Confusion undermines every new compensatory strategy taught that week. Impaired sweating makes an outdoor community-mobility session genuinely dangerous in summer heat. One pharmacological mechanism, five broken occupations.
3. Timing, Grading & Objective Reporting
Session Timing as an Intervention
- Pain medication: schedule ROM, wound care tolerance, and transfer training at the analgesic peak, not at the end of the dosing interval.
- Parkinson's medication: work in the "on" window for motor tasks; use the "off" window deliberately only when the goal is to teach compensatory strategies for the client's worst-case state.
- Sedatives and hypnotics: avoid the hours immediately after dosing for anything requiring balance or new learning.
- Diuretics: anticipate the urgency window and either build toileting into the session or reschedule.
- Insulin and oral hypoglycemics: know when the client last ate and last dosed before a physically demanding session, and recognize hypoglycemia (shakiness, diaphoresis, confusion).
What to Document and Report
Objective, observable, quantified — never a diagnosis:
- ✅ "Client required 3 seated rest breaks and reported dizziness on 2 of 3 sit-to-stand attempts today; BP 96/58 seated after standing trial. Session limited to seated grooming. Nursing and supervising OTR notified."
- ❌ "Client's blood pressure medication is too strong and should be lowered."
The Client-Education Line
Medication management is a genuine occupation — it sits under Health Management in the OTPF-4 — so the COTA absolutely may train a client in the performance of the routine: organizing a pill box, reading and enlarging labels, setting alarms, opening containers with arthritic hands, building the habit into an existing morning routine, and using an automated dispenser. What the COTA may not do is teach what a drug does pharmacologically, what dose to take, or whether to continue it. That content belongs to the prescriber and pharmacist.
A COTA is preparing to work on standing kitchen tasks with a 78-year-old client who takes a loop diuretic each morning, a bladder antispasmodic, and a sedating antihistamine at bedtime. Which combination of adaptations best reflects the COTA's role regarding these medications?
A COTA is grading the intensity of an upper extremity endurance activity for a client with coronary artery disease who takes a beta-blocker. Why is a target heart rate an unreliable way to set intensity for this client?
A COTA is scheduling weekly ADL sessions for a client with Parkinson's disease who takes carbidopa–levodopa four times daily and reports that movement is markedly easier for a period after each dose. When should the COTA schedule motor-intensive dressing and transfer training?
Which documentation entry by a COTA correctly reports a suspected medication-related change in function?