WHAT IS THIS MEDICINE AND WHAT IS IT USED FOR?
Riluzole is the only widely established oral disease-modifying treatment
for amyotrophic lateral sclerosis (ALS) — also known as motor neurone disease
(MND). ALS is a progressive neurodegenerative condition in which the motor
neurones (nerve cells that control voluntary muscle movement) in the brain and
spinal cord gradually deteriorate and die, causing progressive paralysis.
The exact cause is not fully understood, but excessive activity of the
neurotransmitter glutamate is thought to contribute to motor neurone death
(excitotoxicity). Riluzole works by inhibiting the release of glutamate and
blocking certain glutamate receptors, reducing this excitotoxic damage.
Riluzole does not cure ALS or reverse damage already done — but clinical
trials have shown it extends survival by approximately 2 to 3 months on
average, and delays the need for mechanical ventilation. While this may seem
modest, in a condition where no cure exists, it represents meaningful benefit.
It is also used for some other ALS-spectrum conditions at specialist
discretion.
3. HOW TO TAKE THIS MEDICINE
The dose is 50mg twice daily — one tablet in the morning and one in the
evening, approximately 12 hours apart. Riluzole must be taken on an empty
stomach — at least 1 hour before eating or 2 hours after a meal. Food reduces
the absorption of riluzole by approximately 20%, reducing its effectiveness.
Take with a full glass of water. Treatment is continued for as long as it is
considered beneficial — this is an ongoing long-term treatment.
Liver function tests must be performed before starting riluzole and then
monthly for the first 3 months, then every 3 months for the rest of the first
year, then annually. Riluzole can cause elevated liver enzymes and occasional
hepatotoxicity. If liver enzymes rise significantly (more than 5 times the
upper limit of normal), riluzole should be stopped.
⚠ PATIENT TIP: Dizziness and fatigue can be
noticeable in the first few weeks — especially when standing up from sitting
(orthostatic dizziness). Rise slowly from sitting and avoid sudden position
changes. Most people find these effects reduce over time.
4. POSSIBLE SIDE EFFECTS
|
How Common? |
Side Effects |
|
Very Common |
Nausea, fatigue,
dizziness, raised liver enzyme levels on blood tests (usually mild and
transient) |
|
Common |
Diarrhoea, abdominal
pain, increased heart rate (tachycardia), headache, somnolence (drowsiness),
oral numbness or tingling around the mouth, reduced lung function parameters
(in ALS patients) |
|
Serious — Tell Your
Doctor |
Significant liver
toxicity (hepatotoxicity): jaundice, dark urine, severe nausea, right upper
abdominal pain — liver function monitoring is mandatory and dose
suspension/stopping may be required. Neutropenia (low white blood cells) —
rare but potentially serious; report fever, recurrent infections, or mouth
sores. Interstitial lung disease: new cough or breathlessness — rare but
reported. |
5. WHO SHOULD NOT TAKE THIS MEDICINE
Riluzole must not be used in patients with existing significant liver
disease (ALT or AST more than 3 times the upper limit of normal at baseline).
It must be used with caution in patients with kidney disease. It is not
recommended during pregnancy — discuss with your neurologist if this situation
arises. Breastfeeding is not recommended.
⚠ LIVER FUNCTION MONITORING IS MANDATORY: Liver
enzymes (ALT, AST) must be checked before starting, then monthly for 3 months,
then quarterly for 12 months, then annually. If ALT/AST rises to 5 times the
upper limit of normal, riluzole must be stopped — do not miss these blood
tests.
⚠ EMPTY STOMACH REQUIREMENT: Riluzole must
always be taken on an empty stomach — at least 1 hour before eating or 2 hours
after a meal. Food reduces its absorption and effectiveness. This is a simple
but important instruction that significantly affects how well the medicine
works.
⚠ NEUTROPENIA: Although rare, riluzole can
reduce white blood cell counts. Report any fever, recurrent infections, mouth
ulcers, or generally feeling run-down to your neurologist — a blood count will
be needed.
6. MEDICINES THAT INTERACT WITH THIS TREATMENT
CYP1A2 inhibitors (fluvoxamine, enoxacin, ciprofloxacin, caffeine in
large amounts) can significantly increase riluzole levels — use with caution.
CYP1A2 inducers (tobacco smoking, omeprazole, rifampicin, charcoal-grilled
food) reduce riluzole levels and may reduce its effectiveness.
Smoking significantly reduces riluzole plasma levels — smoking cessation
is therefore clinically important and should be encouraged. Hepatotoxic
medicines (amiodarone, allopurinol, methyldopa) increase the risk of liver
damage when combined with riluzole. Alcohol enhances CNS side effects and
increases hepatotoxicity risk — minimise or avoid.
7. HOW TO STORE THIS MEDICINE
Store below 30°C. Keep away from light and moisture. Keep out of reach of
children.
8. PRESCRIPTION REQUIREMENT
|
Field |
Details |
|
Status |
Prescription Only
Medicine (POM) — Specialist (neurology) prescription required; ongoing
prescriptions may be managed by GP with specialist oversight |
9. GUIDANCE FOR PATIENTS & CAREGIVERS
Take one tablet in the morning and one in the evening — always on an
empty stomach, at least an hour before eating. Attend all liver function blood
test appointments — these are essential for your safety on this medicine.
If you smoke, stopping will make riluzole more effective (smoking reduces
blood levels of the drug). Avoid alcohol or keep intake minimal — it increases
liver risk and drowsiness. Rise slowly from sitting or lying down if you feel
dizzy. Report any yellowing of the skin or eyes, dark urine, or unusual fatigue
to your neurologist promptly.
10. PHARMACIST & PRESCRIBER NOTES
|
Field |
Details |
|
Clinical Dispensing
Notes |
Riluzole is the
standard oral DMT for ALS/MND. Empty stomach administration — 1 hour pre-meal
or 2 hours post-meal; food reduces absorption by ~20%. LFT monitoring:
pre-treatment, monthly for first 3 months, every 3 months for months 4–12,
then annually. Suspend if ALT/AST >5x ULN; discontinue permanently if
signs of hepatitis. Neutropenia: rare but monitor — FBC if febrile episodes
or recurrent infections. CYP1A2 interaction: smoking is a significant inducer
— smoking cessation counselling is clinically relevant (improves drug
efficacy). CYP1A2 inhibitors (fluvoxamine, ciprofloxacin) increase riluzole
levels — caution. Hepatotoxic drug combinations (amiodarone, allopurinol) —
increased liver risk. Alcohol: hepatotoxicity and CNS depression. Pregnancy:
not recommended. Dizziness and fatigue counselling on initiation. |
11. FREQUENTLY ASKED QUESTIONS
Q: Does riluzole actually make a difference in ALS?
Riluzole is the only oral medicine shown in clinical trials to extend
survival in ALS — by approximately 2 to 3 months on average. It also delays the
time to needing mechanical ventilation. In a disease where there is currently
no cure and function progressively declines, extending meaningful time is a
genuine benefit. It will not stop the disease or reverse what has already been
lost, but it slows its progression.
Q: Why must it be taken on an empty stomach?
Food reduces how much riluzole is absorbed into the bloodstream by about
20%. Since this medicine is already working to provide a modest benefit, taking
it correctly — on an empty stomach — maximises its effectiveness. It is one of
the few practical things you can control to get the most from the treatment.
Q: Why do I need liver blood tests?
Riluzole can cause elevated liver enzymes and, occasionally, more serious
liver toxicity. Regular blood tests allow early detection — usually before any
symptoms develop — so the dose can be adjusted or stopped if needed. Never skip
these appointments.
Q: Does smoking affect the medicine?
Yes — tobacco smoking activates an enzyme (CYP1A2) that breaks riluzole
down faster, reducing the amount in your bloodstream and potentially reducing
its effectiveness. Stopping smoking will help riluzole work better — and will
benefit your overall health and lung function in ALS too.
Q: How long will I take riluzole?
Riluzole is a long-term treatment taken indefinitely as long as it is
tolerated and considered beneficial. Your neurologist will periodically
reassess whether the benefits outweigh any side effects.