Dabrafenib is an oral drug administered in combination with trametinib.
How it is administered
The dose is 150 mg twice a day. Since each tablet is 75 mg, 2 tablets are taken in the morning and 2 tablets in the evening (12 hours apart). They should be taken between meals (one hour before eating or two hours after eating). The tablets must be swallowed whole with water; they should not be crushed.
If you experience vomiting after taking them, it is not recommended to take the second dose.
Possible side effects of Dabrafenib
Very common side effects
- Fever: a very frequent side effect. If it reaches >38°C, the treatment must be temporarily suspended and an anti-pyretic such as paracetamol should be taken. The responsible doctor must also be advised;
- Squamous Cell Carcinoma of the skin: it is not frequent today thanks to the concomitant administration of trametinib which reduces this risk;
- Skin rash.
Uncommon side effects
- Visual impairment including ophthalmologic reactions such as uveitis, iridocyclitis or iritis
- Reduction in the cardiac ejection fraction
- Kidney failure
- Liver toxicity
- Leukopenia (reduction of white blood cells)
Interactions with other drugs
Dabrafenib is a substrate of CYP2C8 and CYP3A4. Potent inducers of these enzymes should be avoided whenever possible. Dabrafenib itself is an inducer of metabolic enzymes which can decrease other drugs‘ effectiveness. Concomitant use of the following drugs is not recommended:
- phenytoin, carbamazepine or phenobarbital – used for seizures or convulsions;
- ketoconazole, ritonavir, saquinavir, telithromycin, itraconazole, voriconazole, posaconazole and nefazodone – used in the treatment of certain viral and fungal infections;
- rifabutin or rifampicin – used for the treatment of tuberculosis (TB);
- St. John’s wort (Hypericum perforatum) – a herbal medicine used for the treatment of depression;
- warfarin – used for blood clots;
- alfentanil, fentanyl and other painkillers – used for operations;
- rosuvastatin – used to lower the cholesterol level.
Before taking a new drug, contact your doctor to make sure there are no contraindications.
Fertility, pregnancy and breastfeeding
Women are recommended to not become pregnant and men to refrain from conceiving children during treatment with dabrafenib as it may harm the baby.
If there is a possibility that the person taking this drug may become pregnant or become a father, they should use a valid contraceptive method for the duration of the treatment and for at least 90 days after its completion since oral contraceptives may not be effective when taken concomitantly with dabrafenib.