10.1 Epilepsy & Movement Disorders

10.1 Epilepsy & Movement Disorders

Quick Answer: Know the everyday ASMs you will supply — lamotrigine (slow titration; serious rash risk), levetiracetam (behavioural/mood effects), valproate (high teratogenicity → pregnancy-prevention framework), and carbamazepine (enzyme induction, interactions, hyponatraemia). Stress adherence and never abrupt cessation. In Parkinson’s, protect levodopa/carbidopa timing and avoid metoclopramide/other dopamine antagonists that worsen parkinsonism. Driving after seizures is a medical/legal fitness decision — counsel safety at a high level and refer to the treating doctor and current national fitness-to-drive guidance.

Neurology items in the Intern Written exam sit under competency standards 3.2 (implement medication management) and 3.3 (monitor and evaluate). You are not expected to design a full epilepsy work-up; you are expected to counsel safely, spot major interaction and teratogenicity traps, support adherence, and escalate red flags.

Epilepsy — treatment goals and pharmacy role

Epilepsy management aims for seizure control with the fewest adverse effects, using the right drug for the seizure type and patient factors (age, sex, pregnancy potential, comorbidities, interacting medicines, cognitive/mood profile). Many adults are maintained on monotherapy; adjunctive therapy is common when control is incomplete.

Pharmacist high-yield actions:

Common ASMs — counselling and major safety points

Lamotrigine

Lamotrigine is widely used for focal and some generalised epilepsies and as a mood stabiliser in bipolar contexts (confirm indication). Key risk: serious skin reactions (including Stevens–Johnson syndrome / toxic epidermal necrolysis), especially with rapid dose escalation or interacting drugs that raise levels (notably valproate, which inhibits lamotrigine metabolism — titration is slower and target doses differ).

Counselling essentials:

• Start low, go slow — patients must follow the prescribed titration schedule, not “catch up” missed increases casually.
• Report rash, fever, mouth ulcers, eye irritation, or flu-like illness early — stop and seek urgent medical advice if a suspicious rash develops (do not advise restarting without specialist guidance).
• Oral contraceptives and pregnancy planning affect counselling; enzyme inducers and inhibitors change levels — check AMH interaction tables.

Levetiracetam

Levetiracetam is popular because of relatively few pharmacokinetic interactions and straightforward dosing. The main counselling burden is neuropsychiatric effects: irritability, aggression, mood change, anxiety, or rarely suicidal ideation. Ask about mood at supply and review, especially early after initiation or dose increases. Renal impairment may require dose adjustment (AMH).

Valproate (valproic acid / sodium valproate / divalproex formulations)

Valproate is effective for many seizure types but carries major teratogenicity (neural tube defects and other congenital malformations; neurodevelopmental risks). In people who can become pregnant, supply and ongoing dispensing must align with a pregnancy prevention approach: effective contraception, awareness of risks, specialist involvement, and documented risk acknowledgement processes as required by current Australian product information and clinical governance.

Pharmacy exam points:

• Do not treat valproate as a routine “just another tablet” for people of childbearing potential — actively check contraception, pregnancy status where appropriate, and that the patient understands not to stop abruptly if pregnancy occurs without specialist advice.
• Other risks: weight gain, tremor, hair thinning, gastrointestinal upset, hepatotoxicity (especially young children — less common in routine adult community supply but still a monitoring concept), hyperammonaemia, pancreatitis (rare), and thrombocytopenia / bleeding tendency concepts.
• Interactions: enzyme inhibitors/inducers and highly protein-bound drugs can matter; always check combination therapy with other ASMs.

Carbamazepine

Carbamazepine is used for focal seizures and for some neuropathic pain and bipolar indications (confirm). Important concepts:

• Autoinduction — clearance increases over the first weeks; dose adjustments may be planned by the prescriber.
• Enzyme induction — reduces levels/effects of many medicines (oral contraceptives, some anticoagulants, other ASMs, etc.). Counsel on contraceptive failure risk with combined hormonal contraception when enzyme-inducing ASMs are used; discuss reliable alternatives with the prescriber/family planning advice.
• Adverse effects: dizziness, diplopia, ataxia (often dose-related), hyponatraemia, rash (including serious cutaneous reactions; HLA-B*1502 risk is higher in some Asian ancestries — specialist screening concepts), blood dyscrasias (rare).
• Therapeutic drug monitoring may be used in selected situations; interpret with clinical context, not numbers alone.

Adherence, lifestyle, and seizure first aid (high-level)

Adherence is critical. Intermittent dosing, sudden cessation, and binge alcohol can destabilise control. Practical counselling:

• Link doses to daily routines; use dose administration aids when appropriate and safe for the regimen.
• Explain that “feeling well” does not mean epilepsy is cured — most people need ongoing therapy.
• Missed-dose advice is regimen-specific: use AMH and the prescriber’s plan; do not invent double-dosing rules.
• Trigger awareness: sleep deprivation, intercurrent illness, missed doses, alcohol, and flashing lights in photosensitive individuals.

For bystanders and patients: keep the person safe during a seizure, time the event, protect the head, do not put objects in the mouth, and seek emergency care for prolonged seizures, repeated seizures without recovery, injury, or first seizure — align with public first-aid guidance and local protocols.

Driving and seizures — high-level pharmacy advice

Fitness to drive after seizures is governed by medical standards (Austroads / national assessing fitness to drive guidance as applied by state/territory licensing authorities) and the treating doctor’s assessment. Pharmacists should:

• Warn that a recent seizure, medicine change, or new diagnosis may affect legal driving status.
• Strongly advise the patient to discuss driving immediately with their doctor and not drive if instructed not to, or if still recovering from a seizure with impaired alertness.
• Avoid giving personal “clearance” or inventing waiting periods from memory in the exam — the correct answer pattern is safety + medical/legal referral.

Parkinson’s disease medicines — levodopa/carbidopa focus

Parkinson’s disease features bradykinesia, rigidity, tremor, and postural instability, with non-motor features (constipation, sleep disturbance, mood, cognition). Levodopa with a decarboxylase inhibitor (carbidopa or benserazide) remains a cornerstone of motor symptom control.

Counselling and management concepts:

Other Parkinson’s classes (dopamine agonists, MAO-B inhibitors, COMT inhibitors, amantadine, anticholinergics) appear in AMH; exam items often test interaction sense and what not to give rather than full specialist titration.

Putting it together for Intern Written scenarios

Typical stems: a woman of childbearing potential on valproate without contraception discussion; a rash after rapid lamotrigine up-titration; irritability after levetiracetam initiation; hyponatraemia or contraceptive failure with carbamazepine; a patient with Parkinson’s given metoclopramide for nausea; someone driving the day after a seizure. Correct responses prioritise safety frameworks, AMH-guided counselling, interaction avoidance, and timely referral — not improvisational neurology.