Glivec - Dose | Interactions | Side Effects
Glivec comprises a substance called imatinib. It belongs to the group of inhibitors of protein-tyrosine kinase, and works by inducing apoptosis (self-destruction) of leukemic cells. Because of this effect, Glivec is used to treat the following diseases:
- Philadelphia chromosome positive chronic myeloid leukemia (CML) in which bone marrow transplantation cannot be performed
- Philadelphia chromosome positive acute lymphoblastic leukemia (ALL)
- Myelodysplastic disease associated with rearranging genes for the platelet derived growth factor receptors
- Hypereosinophilic syndrome
- Chronic eosinophilic leukemia
- Metastatic, inoperable tumors in the gastrointestinal tract
- Dermatofibrosarcoma protuberans
As you can see, Glivec is used to treat various types of cancers.
When you should take precautions
Glivec should not be used in patients who are hypersensitive to imatinib.
It should never be administered in combination with inducers of enzyme CYP3A4, because these drugs accelerate the metabolism of the Glivec, which decreases its efficiency! Therefore, avoid concomitant use with these drugs:
- The antiepileptic drugs (carbamazepine, phenobarbital and phenytoin)
- Rifampicin (an antibiotic which is used in the treatment of tuberculosis)
- Dexamethasone (a corticosteroid)
- St. John's Wort
Patients who underwent the chirurgical removal of part of the thyroid gland and who are treated with levothyroxine (Euthyrox) must apply this drug very cautiously because of the risk of hypothyroidism. In such patients, regular monitoring of thyroid hormones in the blood is highly recommended.
Given that most of this drug is metabolized by the liver, during treatment, the liver function should be carefully monitored.
Glivec may lead to the occurrence of severe fluid retention in the body which can cause many complications. Sometimes this fluid retention is not manifested with characteristic symptoms, but only by increasing body weight. Therefore, patients should be measured regularly and if you notice a sudden increase in body weight, your doctor should run some tests to determine whether you have fluid retention or not.
Glivec can act negatively on the heart, which is why it is necessary to carefully monitor heart function while you are being treated with this drug.
Glivec, pregnancy and breastfeeding
Glivec should be applied in pregnant women only if the benefit to the mother outweighs the risk to the child. Women who are treated with Glivec must use contraceptive methods.
Breastfeeding should be avoided.
Glivec may be found in the form of tablets and capsules in doses of 100 mg and 400 mg.
The dose is determined based on the individual patient characteristics and the severity of the disease, and the dose can be determined only by doctor who is a specialist in oncology.
It is very important to swallow the tablet/capsule whole with at least two cups of water (500 ml) in order to minimize the gastrointestinal adverse effects.
The tablets should be taken with a meal.
Glivec - interactions with other drugs
In addition to drugs that we've already mentioned earlier in the text, Glivec also should not be used in combination with the following drugs:
- Antibiotics (erythromycin, azithromycin, and clarithromycin)
- Drugs that fight against fungal infections (voriconazole, fluconazole, ketoconazole and itraconazole)
These drugs increase the concentration of Glivec in the blood, thus increasing the risk of side effects.
Glivec can affect the concentration of other drugs, such as:
- Simvastatin (brand names: Atoris and Cholipam) - a drug that is used for hypercholesterolemia. Glivec increases the concentration of simvastatin by 3-5 times, which increases the risk of simvastatin side effects (liver and muscle damage)
- Levothyroxine (Glivec reduces the concentration of this drug)
Glivec side effects
Some of the side effects that Glivec can cause are:
- Abdominal pain
- Muscle cramps
- Tumor hemorrhage
- Fluid retention (pleural effusion, ascites and edema)
- Bone marrow depression
- Infection caused by Herpes zoster virus
- Mood swings (depressed mood and anxiety)
- Increased intracranial pressure
- Edema of the eyelids
- Atrial fibrillation
- Bleeding in the lungs
- Increased pressure in the lungs
- Hair loss
- Breaking nails
- Acute generalized exanthematous pustulosis
- Renal failure
- Sexual dysfunction
- Liver damage