Larotrectinib is used to treat solid tumours that is caused by an alteration or abnormality in a gene known as neurotrophic tyrosine receptor kinase (NTRK).
It is used for those who have tumour that has spread to other parts of the body, or if a surgical removal of the cancer may cause complications, have no acceptable treatment options, or those whose tumours have progressed after previous therapy.
Take Larotrectinib exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.
You may take this medicine with or without food. Try to take it at the same time each day.
Larotrectinib is available as a capsule or an oral solution.
If you are taking the capsule, swallow it whole with a glass of water. Do not chew, crush or open the capsule.
If you have been given the oral solution, follow these steps:
- Open the bottle by pressing the cap and turning it anticlockwise.
- Use the oral syringe supplied with each bottle to measure out your dose.
- Put the bottle adapter into the bottle neck and make sure it is fixed well.
- Push the plunger fully into the syringe, then put the syringe in the adapter opening.
- Fill in the syringe with the appropriate dose by pulling the plunger down, then push the plunger upwards to remove any large bubbles that are in the syringe. Pull the plunger down to the mark equal to the dose in mL prescribed by your doctor. Turn the bottle the right way up and take the syringe out of the adapter.
- Administer the medicine directly from the oral syringe. Put the syringe in your mouth. Point it towards the inside of your cheek, then slowly press the plunger in.
- Put the bottle cap on and tightly close the bottle. Leave the adapter in the bottle. If necessary insert it into the perforated stopper and turn the bottle upside down.
- Wash the oral syringe after use.
Larotrectinib may also be given via nasogastric tube. Do not mix the dose with feeding formulas as it may lead to blockage of the feeding tube.
Make sure you know how to administer this medicine with the oral syringe or feeding tube. If you have problems or do not understand the instructions, ask your doctor or pharmacist.
If you vomit after taking a dose of this medicine, do not repeat the dose. Take the next dose at your normal scheduled time.
The dose of this medicine will be decided by your doctor. Your doctor will advise you on the treatment timeframe depending on your condition and response to the medication.
Larotrectinib must be taken regularly for it to be effective. Continue taking this medicine even when you feel better. Do not stop taking it unless instructed by the doctor.
If you missed a dose, take it as soon as you remember. If the next scheduled dose is due within 6 hours, skip the missed dose and return to your normal dosing schedule.
DO NOT double a dose under any circumstances.
If you often forget to take your medicine, let your doctor and pharmacist know.
Do not take this medicine if you are pregnant. If you become pregnant while on Larotrectinib therapy, alert your doctor immediately. This medicine may cause harm to your unborn child.
It is important that you do not get pregnant while taking this medicine. Both men and women must use proven birth control methods during Larotrectinib therapy and for at least 1 month after stopping the treatment. Birth control medicines containing hormones may not be effective. You may wish to discuss other reliable methods of birth control with your doctor.
Do not breastfeed while you are being treated with Larotrectinib and for at least 1 week after stopping the treatment.
Inform your doctor if you have a moderate to severe liver disease.
Be sure to check with your doctor or pharmacist before giving Larotrectinib to a child. Children may be more sensitive to the side effects.
Why is it important to keep my appointments with the doctor?
Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly.
- Confirmatory test to verify the presence of NTRK gene and pregnancy tests must be done before treatment to know if this medicine is suited for you to take.
- Your doctor may need to perform blood tests to make sure that your liver function is normal before you take Larotrectinib and thereafter depending on your doctor’s advice.
Larotrectinib may cause dizziness or tiredness. If affected, do not drive or take part in any activity in which you need to be alert.
Other side effects include any of the following: headache, cough, stuffy nose, constipation, nausea, vomiting, diarrhoea, stomach pain, altered taste, weight gain, and muscle, back or joint pain.
Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
- yellowing of the skin or eyes, dark coloured urine, swelling in the legs and ankles
- feeling confused, unusual changes in mood or behaviour, problems with concentration and memory
- bone pain, changes in your ability to move around
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Inform your doctor and pharmacist if you are taking any of these medicines:
- medicines to treat fungal infection e.g. itraconazole, ketoconazole, voriconazole
- certain antibiotics e.g. clarithromycin, telithromycin
- medicines for HIV infection e.g. atazanavir, nelfinavir, ritonavir, saquinavir
- medicines used in organ transplant or certain immune disorders e.g. ciclosporin, sirolimus, tacrolimus
- medicines for epilepsy (fits or seizures) e.g. carbamazepine, phenobarbital, phenytoin
- medicines for migraine e.g. ergotamine, dihydroergotamine
- strong painkillers e.g. fentanyl, alfentanil
- rifampicin (medicine to treat TB, infection known as tuberculosis)
- quinidine (medicine for irregular heartbeat)
- St. John’s wort (herbal medicine)
This list does not include all medicines that may interact with Larotrectinib.
Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements, and medicines that you buy without a prescription.
Avoid excessive consumption of grapefruit or grapefruit juice.
Store the capsule in a cool, dry place away from the reach of children.
The oral solution must be stored in the refrigerator, between 2-8°C. Do not allow to freeze. If frozen, this medicine will become ineffective and should not be used.
Medicines must not be used past the expiry date.
As this is a cancer medicine, always return any unused or expired capsules or solution to the clinic, hospital or pharmacy for disposal. Do not throw it away in the household waste.