WHAT IS THIS MEDICINE AND WHAT IS IT USED FOR?
Pazonix contains pazopanib, a targeted cancer medicine that blocks
several proteins (called receptor tyrosine kinases, including VEGFR, PDGFR, and
c-KIT) that cancer cells and nearby blood vessels use to grow and form new
blood vessels.
Without a blood supply, tumours cannot get the nutrients they need to
grow and spread.
Pazopanib is used in adults for: advanced renal cell carcinoma (kidney
cancer) — as a first-line treatment or after previous immunotherapy; and
advanced soft tissue sarcoma (a type of cancer affecting muscles, fat, tendons,
and other connective tissues) — in patients who have had prior chemotherapy.
The 400mg tablet is more convenient for patients on the standard 800mg
daily dose — instead of taking four 200mg tablets, they take two 400mg tablets.
3. HOW TO TAKE THIS MEDICINE
Standard dose: two 400mg tablets once daily (800mg total), taken on an
empty stomach — at least 1 hour before or 2 hours after eating. If a dose
reduction is required (to 600mg or 400mg), the 200mg tablet will likely be
prescribed instead for greater flexibility. Swallow whole with water. Do not
crush or break. Take at the same time each day.
The 400mg tablet is primarily a convenience formulation for patients
stable on the standard 800mg dose.
⚠ PATIENT TIP: Taking two tablets instead of
four is a practical improvement in your daily routine — but all the safety
monitoring and precautions remain exactly the same. Continue daily blood
pressure checks, attend all liver function appointments, and report any new
symptoms as described for the 200mg tablet.
4. POSSIBLE SIDE EFFECTS
POSSIBLE SIDE EFFECTS
|
How Common? |
Side Effects |
|
Very Common |
High blood pressure
(hypertension — very common, affecting most patients), diarrhoea, hair colour
changes (depigmentation — hair may turn lighter or grey-white), nausea,
fatigue, decreased appetite, vomiting, weight loss, raised liver enzymes on
blood tests |
|
Common |
Headache, taste
changes (metallic or reduced taste), skin problems (rash, hand-foot syndrome
— redness and soreness on palms and soles), hypothyroidism (underactive
thyroid), raised blood sugar |
|
Serious — Tell Your
Doctor Right Away |
Liver toxicity
(hepatotoxicity): jaundice (yellow skin or eyes), dark urine, right-sided
tummy pain — can be severe and occasionally fatal; requires urgent review and
possible treatment discontinuation. Severe high blood pressure or
hypertensive crisis. Arterial thromboembolism (heart attack, stroke — sudden
chest pain, weakness, speech difficulty). Tumour-related bleeding. QT
prolongation (heart rhythm change). Gastrointestinal perforation or fistula
(severe abdominal pain). |
5. WHO SHOULD NOT TAKE THIS MEDICINE
Pazopanib should not be used during pregnancy — it can seriously harm an
unborn baby. Effective contraception is essential during treatment and for at
least 2 weeks after the last dose.
It must be used with extreme caution — or avoided — in patients with
significant liver impairment (it is primarily processed by the liver). Do not
use in patients with a recent history of heart attack, stroke, or serious
haemorrhage.
⚠ LIVER TOXICITY: This is the most serious
safety concern with pazopanib. Liver enzyme tests (ALT, AST) must be checked
before treatment, then at weeks 3, 5, 7, and 9, then monthly for the first
year. Liver failure has occurred. Report any jaundice, dark urine, or severe
fatigue immediately.
⚠ BLOOD PRESSURE MONITORING: Monitor blood
pressure daily at home and keep a log. High blood pressure must be treated
promptly — it increases the risk of stroke and heart attack. If BP exceeds
150/100 mmHg, contact your care team.
⚠ EMPTY STOMACH: Always take pazopanib on an
empty stomach. A high-fat meal increases absorption dramatically and can cause
unpredictable and dangerous drug levels.
6. MEDICINES THAT INTERACT WITH THIS TREATMENT
Strong CYP3A4 inhibitors (ketoconazole, ritonavir, grapefruit juice,
clarithromycin) significantly raise pazopanib levels — avoid these. Strong
CYP3A4 inducers (rifampicin, phenytoin, carbamazepine, St. John's Wort) reduce
efficacy — avoid.
Pazopanib itself inhibits CYP enzymes and may raise levels of statins
(particularly simvastatin) and other CYP substrates — discuss all medicines
with your oncologist. QT-prolonging medicines increase cardiac risk. Proton
pump inhibitors (omeprazole) reduce pazopanib absorption — avoid or take
pazopanib at a specific time relative to the PPI.
7. HOW TO STORE THIS MEDICINE
Store below 25°C in original packaging. Keep away from moisture and
light. Keep out of reach of children.
8. PRESCRIPTION REQUIREMENT
|
Field |
Details |
|
Status |
Prescription Only
Medicine (POM) — Specialist (oncology) prescription required |
9. GUIDANCE FOR PATIENTS & CAREGIVERS
Take your tablets on an empty stomach — at least 1 hour before eating or
2 hours after a meal — at the same time each day. Check your blood pressure
every day and keep a written log to share with your oncology team.
Attend all liver function blood test appointments without fail. Report
any yellow discolouration of skin or eyes, dark urine, or severe right-sided
tummy pain to your oncologist immediately.
Protect your hands and feet with thick moisturiser to manage hand-foot
syndrome. Avoid grapefruit. Use effective contraception throughout treatment.
10. PHARMACIST & PRESCRIBER NOTES
|
Field |
Details |
|
Clinical Dispensing
Notes |
Fasting administration
is critical — food (especially high-fat meal) dramatically increases AUC. LFT
monitoring schedule: pre-treatment, weeks 3, 5, 7, 9, then monthly for 12
months — hepatotoxicity is the primary safety concern and can be fatal. BP
monitoring: daily home monitoring, treat hypertension promptly. CYP3A4
interaction screening mandatory — avoid strong inhibitors and inducers.
Grapefruit counselling. PPI interaction: advise separation or switch to
short-acting H2 blocker taken in morning. Statin interaction (especially
simvastatin, atorvastatin) — dose reduction may be needed. QT-prolonging drug
interaction check. Embryo-fetal toxicity — contraception during and 2 weeks
post-treatment. Hand-foot syndrome prevention counselling. Hair depigmentation
— common and benign; counsel proactively. |
11. FREQUENTLY ASKED QUESTIONS
Q: Why must I take both tablets at the same time?
Pazopanib needs to be taken once daily as a single dose at the same
consistent time each day — ideally on an empty stomach. Splitting the dose
across the day is not recommended as it changes the absorption pattern.
Q: Can I take the two tablets at night?
Evening dosing is possible for some patients — particularly if you prefer
to take it well after your evening meal (ensuring the stomach is empty).
Discuss the best timing for your schedule with your oncologist, keeping in mind
the fasting requirement.
Q: Is the liver monitoring the same as for the 200mg tablet?
Yes — the same monitoring schedule (pre-treatment, weeks 3, 5, 7, 9, then
monthly) applies regardless of which tablet strength you take. The dose and
schedule of liver tests are based on the medicine, not the tablet size.