Tykerb 250 Tablet

Description of Tykerb 250 (Lapatinib 250 mg) tablet

An antineoplastic drug called Lapatinib, Lapatinib is classified under the category of antineoplastic agent drugs (anti-cancer). Tykerb 250 contains the active ingredient of Lapatinib 250mg and pharmacologically classified as a tyrosine kinase inhibitor (TKI). It is particularly applied in treating breast cancer that is positive in HER2. Lapatinib action is through the inhibition of two important cancer cell growth factors popularly referred to as epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2). The drug inhibits the growth of cancer cells and slows down tumor development by inhibiting these signaling pathways. Lapatinib is a small molecule as compared to monoclonal antibodies which act inside the cell and in this case, it finds application in cancers which are resistant.

It is particularly applied in treating breast cancer that is positive in HER2. Lapatinib action is through the inhibition of two important cancer cell growth factors popularly referred to as epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2). The drug inhibits the growth of cancer cells and slows down tumor development by inhibiting these signaling pathways. Lapatinib is a small molecule as compared to monoclonal antibodies which act inside the cell and in this case, it finds application in cancers which are resistant.

Indications of Tykerb 250 (Lapatinib 250 mg) tablet

Lapatinib is coordinated to treat the breast cancer in patients that are HER2-positive, advanced or metastatic and specifically in the patients who have gone through other treatments, such as trastuzumab or the chemotherapy.

Mechanism of action of Tykerb 250 (Lapatinib 250 mg) tablet

Lapatinib is an anti-cancer medication that inhibits the intracellular receptors to tyrosine kinase such as the HER2 and EGFR receptors. The signaling pathways, which increase the survival and growth of the cancer cells, involve these receptors. The Lapatinib blocks a downstream signaling that transpires following these receptors by inhibiting their phosphorylation and activation, which leads to tumor growth inhibition and induction of apoptosis.

How to consume Tykerb 250 (Lapatinib 250 mg) tablet

It is to be taken on an empty stomach, at least 1 hour before or after food since food could multiply the absorption and toxicity of the drug many times.

Side Effects of Tykerb 250 (Lapatinib 250 mg) tablet

1. Common Side Effects

• Diarrhea
• Nausea
• Vomiting
• Rash
• Fatigue

2. Serious Side Effects

• Hepatotoxicity
• Cardiotoxicity
• Severe diarrhea leading to dehydration
• QT prolongation

3. Rare Side Effects

• Interstitial lung disease
• Hypersensitivity reactions

Safety Advice for Tykerb 250 (Lapatinib 250 mg) tablet

Lapatinib is also liver and heart sensitive and therefore, the drug should be carefully monitored by frequently conducting liver and heart functioning tests in the patients.

Breastfeeding: Lapatinib should not be taken when lactating since it can be transferred to the breast milk thus affecting the baby.

Pregnancy: Not advisable since it can lead to damage to the unborn baby.

Alcohol: Alcohol is not to be taken as it can augment liver toxicity and augment side effects.

Liver: Lapatinib can cause hepatotoxicity which can be fatal or severe. Liver enzyme levels also should be checked periodically when taking medication.

Lungs: The patients are to report cough or breathlessness, where there are some rare cases of interstitial lung disease.

Kidney: No dose change that is normally required is present but in severe cases of renal impairment, care should be observed.

Driving: The patients can be fatigued or even dizzy; they should not drive when they feel that way.

Interaction of Tykerb 250 (Lapatinib 250 mg) tablet

• Drug–Drug Interaction

Itraconazole × Lapatinib These medications block Lapatinib metabolism, leading to high plasma concentrations and hepatotoxicity and QT prolongation.

• Carbamazepine × Lapatinib

These medicines raise the metabolism of Lapatinib, which makes it ineffective.

QT-prolonging drugs × Lapatinib

Additive QT prolongation effects may lead to risk of cardiac arrhythmias with concurrent use.

• Capecitabine × Lapatinib

Widely used combination, although can lead to greater gastrointestinal toxicity, like diarrhea.

Antacids × Lapatinib

May interfere with absorption and diminish the effectiveness of drugs.

• Drug–Food Interaction

Lapatinib is strongly absorbed by food, and can be toxic. It must therefore always be taken on empty stomach. Grapefruit juice should be avoided as it inhibits CYP3A4 and increases drug levels.

• Drug–Disease Interaction of Tykerb 250 (Lapatinib 250 mg) tablet

Liver disease:
The metabolism of Lapatinib takes place in the liver and liver dysfunction may raise the concentration of this drug and cause liver toxicity. Dose adjustment and monitoring is necessary.

Cardiac disease:
Lapatinib can lead to a reduction of the left ventricular functioning as well as to the QT protruding. Patients that have already a diseased heart should be closely supervised.

Gastrointestinal disorders:
Intensive diarrhea that may exacerbate underlying GI disorders resulting in the electrolyte imbalance and dehydration is one of the side effects.

Electrolyte imbalance:
Hypokalemia or hypomagnesemia could increase the risk of potential risks of QT prolongation and cardiac arrhythmias.

Contraindication of Tykerb 250 (Lapatinib 250 mg) tablet

Not to be used when there is hypersensitivity and severe liver impairment.

Dosage of Tykerb 250 (Lapatinib 250 mg) tablet

It depends on the dosage of the combination therapy and patient condition.

Storage of Tykerb 250 (Lapatinib 250 mg) tablet

Store at room temperature, dry and do not heat.

Missed Dose of Tykerb 250 (Lapatinib 250 mg) tablet

When there is a missed dose, then skip the missed dose and continue with the next dose.

Other General Information of Tykerb 250 (Lapatinib 250 mg) tablet

Patients are supposed to keep hydrated and notify about severe diarrhea jaundice or cardiac symptoms as soon as possible. Constant check-ups are necessary.

FAQs of Tykerb 250 (Lapatinib 250 mg) tablet

1. Why is Lapatinib better taken on an empty stomach?

Since food greatly enhances its absorption which may result in increased drug concentrations and toxicity.

2. Why is liver monitoring important?

Lapatinib has the potential to induce hepatotoxicity that can be potentially fatal in case it is not timely diagnosed.

3. Does Lapatinib have any heart effects?

Yes, it may lead to a reduction in cardiac activity and the QT prolongation, which needs routine observation.

4. What is the common diarrhea with Lapatinib?

Since it targets fast dividing cells of the gastrointestinal tract, causing irritation and loss of fluids.

5. What is the purpose of combination therapy?

Since Lapatinib is more effective in combination with other anticancer drugs, enhancing the effectiveness of the treatment.

Fact Box of Tykerb 250 (Lapatinib 250 mg) tablet

References

• FDA Prescribing Information – Lapatinib
  https://www.accessdata.fda.gov/drugsatfda_docs/label/2023/022059s027lbl.pdf
• European Medicines Agency (EMA) – Lapatinib Product Information
  https://www.ema.europa.eu/en/documents/product-information/tyverb-epar-product-information_en.pdf
• DrugBank – Lapatinib
  https://go.drugbank.com/drugs/DB01259
• National Cancer Institute (NCI) – Lapatinib
  https://www.cancer.gov/about-cancer/treatment/drugs/lapatinib