Polypharmacy in Geriatric Neurology: Risks & Management

Challenges of polypharmacy in a geriatric patient with neurological disorder

Nandakumar

Clinical Pharmacist, Kauvery Hospital Radial Road, Chennai, Tamil Nadu

Introduction

Polypharmacy is the concurrent use of five or more medications, is a growing concern in geriatric care due to the high prevalence of chronic disease and age related physiological changes. Among elderly patients with neurological disorders, such as Parkinson’s disease, dementia, stroke, or epilepsy, the risk of polypharmacy is particularly significant. Cognitive and functional impairments associated with neurological disorders further complicate safe medication management, heightening the risk of hospitalizations, reduced quality of life, and increased healthcare costs. Addressing these challenges is crucial to optimizing therapeutic outcomes while minimizing harm, making polypharmacy a central issue in geriatric neurology and multidisciplinary care.

Justification

Patient came to ER with a complaint of altered sensorium and decreased food intake with tremors and also developed one episode of seizure one week ago. Then he was on antiepileptic drug and in view of low GCS patient was intubated and He developed persistent right upper limb and lower limb jerky movements, reduced responsiveness followed by up rolling of eye refractory to multiple ASM. He was admitted for further evaluation and management.

Diagnosis

Parkinson’s disease
Status epilepticus
Bipolar effective disorder
CAD/DM/HTN

Medications

S.No	Medication	Dose	Frequency	Duration
1	Tab. levetriacetam	750mg	1-0-1	2 month
2	Tab. lacosamide	100mg	0-0-1/2	1 month
3	Tab. clobazam	10mg	0-0-1	2 month
4	Tab .zonisamide	100mg	1-0-1	2 month
5	Tab. perampanel	2mg	0-0-1	2 month
6	Tab. syndopa	110mg	1/2-1/2-0	2 month
7	Tab. tetrabenazine	25mg	1/2-0-1/2	2 month
8	Tab. bromocriptine	1.25mg	1-0-1	2 month
9	Tab. modafinil	100mg	½-0-0	1 month
10	Tab. Addna	1gm	1-0-1	2 month

Prescription of Two (Or) More ASM (Anti-Seizure Medications)

These are medications used to prevent (or) reduce seizures in people with epilepsy/seizure disorder

Why Two (Or) More ASM May Be Used?

Many people respond well to a single ASM (Monotherapy), If a seizure continue despite one drug at the right dose, doctor may add a second ASM (Dual therapy) (or) even more (Poly therapy).

Risk and Considerations

Using two (or) more ASM can increase side effects such as sleepiness, dizziness, memory problems, mood changes etc., So doctor should carefully select combination that work will together and avoid interactions.

In sometimes poly therapy improve seizure control, when monotherapy fails

Why Combines ASM?

Seizure persist despite optimized monotherapy; this idea is to use drugs with different mechanisms of action so they complement each other. Avoid combining two with similar mechanisms. Because, it usually increases side effects without better control.

So combination generally avoided are,

Two Sodium channel blockers (Carbamazepine + phenytoin + Lamotrigine) overlapping toxicity.
Sodium valporate +Topiramate – Risk of Hyper ammonemic encephalitis.
Multiple sedating agents (Valporate + Phenobarbitone + Benzodiazepines) results in excessive drowsiness and cognitive decline.

Commonly used ASMs

Some major classes and examples

Sodium channel blockers: – Carbamazepine, Phenytoin, Lamotrigine, Lacosamide
Calcium channel blocker:-(T-type) Ethosuximide – Especially in treating Absence seizure.
GABA enhancers: – Sodium valproate, Benzodiazepines (Clobazam, clonazepam), Phenobarbital, Tiagoline.
SV2A (Synaptic vesicle glycoprotein 2A) binding drugs – Levitriacetam, Brivaracetam.
Others/Mixed medications- Topiramate, Zonisamide, Perampanel.

Looking into the patient medications, it includes one sodium channel blocker, one SV2A binding drugs, one GABA enhancers and newer agents all have different mechanisms.

Drugs for The Management of Parkinson’s Disease

Syndopa 110 mg is the combination of Dopamine precursor and Peripheral decarboxylase inhibitors. Levodopa crosses the blood brain barriers and being converted into dopamine inside the brain. Carbidopa prevents the premature conversion of the drug levodopa into dopamine outside the brain.
Tetrabenazine is VMAT2 – Vesicular monoamine transporter 2 used to control symptoms of Parkinson’s disease, It control sudden involuntary movements(chorea) it was formerly used as a anti psychotic, But now Primarily used in the symptomatic treatment of various hyperkinetic disorders.
Bromocriptine acts by irreversibly inhibits the activity of monoamine oxidase type B –the enzyme that breaks down dopamine, thereby increasing dopaminergic action.
Modafinil is to prevent the Day time sleepiness produced by the ASM and Benzodiazepines. Tab. ADDNA is used to increase the serum sodium level, Patient has 136 mEq/L.

Clinical pharmacist recommendation

Together administration of levitriacetam and zonisamide (Moderate risk) may increase the risk of CNS depression and cognitive impairments so it is always recommended to monitor for signs of excessive sedation and drowsiness
Administration of Clobazam (benzodiazepines)with Perampanel (AMPA receptor agonist) may produce additive and synergistic CNS and Respiratory despression, also lead to impairment in thinking, judgement, motor co-ordination and dizziness. Pharmacodynamic summation – Different target but same outcome, Clobazam increases inhibitory tone(GABA) and Perampanel reduces excitatory tone (Glutamate). Pharmacokinetic caveats Perampanel metabolism and Clobazam metabolites are influenced by Cytochrome enzymes (CYPs) when one drug markedly raises the other’s blood levels – thereby increase sedation risk

Conclusion

Age related physiological changes further complicate pharmacokinetics and pharmacodynamics, making this population highly vulnerable. Careful medication reconciliation, regular review of drug regimens, de prescribing when appropriate and interdisciplinary collaboration are essential to minimize harm and optimize therapeutic outcomes. Ultimately, a patient centered individualized approach is key to balancing symptom control with quality of life in elderly patients living with neurological conditions.

Challenges of polypharmacy in a geriatric patient with neurological disorder

Challenges of polypharmacy in a geriatric patient with neurological disorder

Nandakumar

Nightingale Journals