Medication Stock-Outs and Epilepsy Supply-Chain Failure

An antiseizure medicine can be clinically effective and still fail a patient if the supply chain cannot deliver it. Stock-outs, shortages, unaffordable prices and disrupted distribution are major but under-recognised causes of treatment interruption worldwide.

What is a stock-out?

A stock-out occurs when a medicine that should be available is temporarily unavailable at the point where it is normally supplied.

The problem can occur nationally, regionally, in a hospital, in a pharmacy or within one formulation or strength.

Why antiseizure medicines are especially sensitive to interruption

Epilepsy treatment usually depends on regular dosing.

Missing doses can increase seizure risk, and abrupt withdrawal of some medicines may provoke seizure clusters or status epilepticus.

Global access is already uneven

WHO reports that access to essential neurological medicines remains a major global health challenge.

In many low-resource settings, some first-line antiseizure medicines are intermittently unavailable or unaffordable even before a formal shortage occurs.

The supply chain is international

Active ingredients, finished dosage forms, packaging and distribution may occur in several countries.

A disruption at one manufacturer can therefore affect patients thousands of kilometres away.

Manufacturing concentration creates vulnerability

A 2024 analysis of US generic antiseizure-medicine supply chains found substantial concentration of manufacturing and limited transparency in parts of the system.

The study also noted a small number of facilities producing some parenteral antiseizure formulations, which can increase vulnerability when one site fails.

Why shortages happen

Causes include manufacturing problems, quality failures, shortages of active ingredients, commercial withdrawal, regulatory delays, transport disruption, conflict, disasters and sudden changes in demand.

Formulation matters

A tablet may remain available while a liquid, injectable or specific dose strength is unavailable.

This particularly affects children, people with swallowing difficulties and emergency treatment.

Brand and generic changes

During shortages, patients may be offered a different manufacturer or formulation.

For many antiseizure medicines generic substitution is appropriate, but changes should still be explained clearly because appearance, excipients and dosing devices can differ.

Do not ration by skipping doses

People should not try to make medication last longer by taking fewer tablets or changing dose intervals without clinical advice.

This can produce unstable drug concentrations and breakthrough seizures.

What health systems can do

Strategies include better forecasting, minimum stock requirements, multiple suppliers, transparent shortage reporting, emergency procurement and protection of essential neurological medicines in national formularies.

What clinicians can do

Prescribers can document acceptable alternatives, avoid unnecessary formulation changes and provide clear conversion instructions when substitutions are unavoidable.

Controlled medicines

Some seizure rescue medicines and antiseizure drugs are controlled substances in certain jurisdictions.

WHO’s 2025 guidance on controlled medicines emphasises the need to balance safe regulation with reliable medical access.

Humanitarian emergencies

Conflict and disaster can magnify ordinary supply-chain weakness.

Even when medicines are donated, mismatched formulations, short expiry dates or lack of distribution infrastructure can limit usefulness.

The central point

Treatment failure is not always pharmacological failure. Sometimes the medicine works, but the health system cannot supply it consistently.

Sources

Medical note: prescribed antiseizure medication should not be reduced or stopped because of a shortage without advice from a clinician or pharmacist.

Evidence checked: September 2026.