Anti-Seizure Medicines: The Dispensing Safety Checklist

📋 First Dispense Essentials

Mandatory items to issue

• Valproate only: dispense in the manufacturer's original full pack (legal requirement since October 2023 in England, Scotland and Wales). Do not re-pack into plain dispensing containers. Round up or down to supply complete packs only. An exception applies only in exceptional circumstances where an individual risk assessment supports it and the Patient Information Leaflet is supplied in the pack.
• Valproate only: confirm the patient card and Patient Information Leaflet are in the pack. If the card is missing, source a replacement from the MHRA or the manufacturer before dispensing.
• For Category 1 drugs (phenytoin, carbamazepine, phenobarbital, primidone): check the PMR to confirm what brand, manufacturer, and formulation were supplied previously. If the prescription does not state a specific brand, maintain continuity with the previous supply and record what was dispensed. If the previous brand or manufacturer cannot be confirmed, contact the prescriber before supply unless an urgent professional judgement supply is needed to avoid missed doses.

Baseline clinical checks

• Confirm the indication is epilepsy. MHRA brand-switching rules apply only for epilepsy, not for other uses of the same drug (for example, carbamazepine for neuropathic pain or valproate for mood disorder).
• Valproate in women and girls of childbearing potential: confirm the Pregnancy Prevention Programme (PPP) is in place. The PPP requires an annual risk acknowledgement form signed by both patient and prescriber, effective contraception, and a specialist review.
• Valproate under-55 new initiation rule (all patients, from January 2024): valproate must not be initiated in any new patient under 55 unless two specialists independently confirm no other effective or tolerated treatment exists. This two-specialist requirement applies to new initiations only. Men already taking valproate do not require a two-specialist review (MHRA clarification, February 2025).
• Valproate male patients (from September 2024): men taking valproate and their partners should use effective contraception during treatment and for at least 3 months after stopping, because of a possible increased risk of neurodevelopmental disorders in children fathered by men taking valproate. Men should not donate sperm during treatment or for at least 3 months after stopping.
• Carbamazepine new starts: check whether the patient is of Han Chinese or Thai origin. These patients should be screened for the HLA-B*1502 allele before starting, due to a significantly increased risk of Stevens-Johnson syndrome.

Key risks and lifestyle traps

• <strong>Category 1</strong> (always maintain manufacturer's product): phenytoin, carbamazepine, phenobarbital, primidone. <strong>Category 2</strong> (maintain where possible; switch only after prescriber agreement and patient discussion, with documented clinical justification): valproate, lamotrigine, topiramate, oxcarbazepine, clobazam, clonazepam, zonisamide, perampanel, eslicarbazepine, rufinamide. <strong>Category 3</strong> (generic usually acceptable; patient-specific factors apply): levetiracetam, lacosamide, gabapentin, pregabalin, ethosuximide.
• Modified-release formulations (for example, carbamazepine modified-release, valproate modified-release) must be maintained on the same product brand and formulation as well as manufacturer. Switching between standard-release and modified-release is not interchangeable.
• Enzyme-inducing medicines (carbamazepine, phenytoin, phenobarbital) reduce the effectiveness of hormonal contraceptives and interact with many other medicines including anticoagulants. Check for new co-prescriptions at every dispense.
• Valproate increases lamotrigine concentrations significantly, raising the risk of serious skin reactions and toxicity. Any dose change to either drug requires careful monitoring.

First dispense script

🔄 Repeat Dispense Screen

Mandatory documentation

• Record the brand name, manufacturer, and formulation dispensed on every occasion in the product notes and patient medication record, especially where the prescription is written generically. If a different brand was supplied due to shortage, document the reason, the prescriber contacted, and the outcome.
• For valproate: ask or check whether the annual specialist review and risk acknowledgement are current. If overdue or unclear, escalate to the prescriber before dispensing.

Ongoing clinical checks

• Check the PMR to confirm the brand, manufacturer, and formulation match what was dispensed previously. Any change for Category 1 or 2 drugs requires prescriber agreement before supply.
• Be alert to patients who have recently had a hospital discharge, a specialist clinic change, or a care-home supply change: these are common sources of unintended brand switching.
• Drug shortage: before substituting a brand, check the NHS Specialist Pharmacy Service (SPS) Medicines Supply Tool at sps.nhs.uk for current information and alternative supplier details. Contact the prescriber before making any switch.
• If no supply can be obtained: do not leave the patient without medicine. Contact the prescriber immediately to arrange an emergency prescription or urgent alternative supply.
• Enzyme inducers: check for any new medicines on the patient record that may interact; particularly antibiotics, antifungals, and newly started anticoagulants.

Ask the patient at the counter

• "Have you had any new seizures, or more seizures than usual, since your last supply?"
• Valproate patients of childbearing potential: "Are you pregnant, or could you become pregnant?" If yes, escalate urgently to the prescriber or specialist before making a supply decision. Do not advise abrupt discontinuation.

Lifestyle and surgical alerts

• Driving regulations apply following seizures. Any deterioration in seizure control must be reported to the prescriber promptly.
• Alcohol may increase sedation and can worsen seizure control.
• Any patient who is pregnant or planning pregnancy should be referred promptly to their specialist or prescriber for review.
• Anti-seizure medicines must never be stopped suddenly without prescriber guidance. Abrupt discontinuation can trigger status epilepticus.

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