A daily targeted pill for ALK-positive lung cancer, usually well tolerated. Common effects are tiredness, constipation, muscle aches, and swelling. Your team checks bloodwork often in the first months to catch liver or muscle-enzyme rises early.

Oral alectinib taken twice daily, continuously (an ALK-targeted pill). Generally well tolerated. Liver-enzyme and muscle-enzyme (CPK) rises tend to appear in the first weeks-months, so bloodwork is checked often early. Onset is measured in weeks-months, not infusion cycles.

What is reported

This regimen is taken continuously, so effects are described in the terms their sources use rather than by cycle day.

Elevated liver enzymes (hepatotoxicity)

~72% within the first 3 months

Rises in liver blood tests (AST/ALT/bilirubin), usually without symptoms and most often in the first 3 months. Your team checks bloodwork every 2 weeks early on and adjusts the dose if needed. Report yellowing of skin/eyes or belly pain.

Call your team: Yellowing of skin/eyes, dark urine, or severe belly pain.

reported by about 40-54% (AST/ALT/bilirubin) of people; severe in 5-6% · from Alectinib

Anemia

A drop in red cells that can cause tiredness and breathlessness, developing over the first weeks-months.

Call your team: New or worsening breathlessness or a racing heart.

reported by about 62% of people; severe in 7% · from Alectinib

Muscle aches with CPK rise (myalgia/myositis)

early (median ~15 days for grade 3+ CPK)

Muscle aches, sometimes with a rise in the muscle enzyme CPK on bloodwork. It tends to appear early (median ~2 weeks for higher rises). Report unexplained muscle pain, tenderness, or weakness; your team checks CPK.

reported by about 23-37% (myalgia/CPK) of people; severe in 2.8% · from Alectinib

Constipation

A common, usually manageable effect. Fluids, fiber, activity, and laxatives as advised help.

reported by about 34% of people; severe in 0% · from Alectinib

Fatigue

Tiredness that builds over the first weeks-months and persists while on the drug. Pace activities and rest as needed.

reported by about 26% of people; severe in 1.3% · from Alectinib

Swelling (edema)

builds over weeks-months

Fluid swelling of the ankles, legs, eyelids, or face that can build over weeks-months. Leg elevation and reducing salt help; report rapid swelling or breathlessness.

reported by about 22% of people; severe in 0.7% · from Alectinib

Slow heart rate (bradycardia)

any time during daily dosing

The heart rate can slow, usually without symptoms. Your team checks heart rate and blood pressure and reviews other rate-slowing medicines; report dizziness or fainting.

reported by about 11% of people · from Alectinib

Photosensitivity (sun sensitivity)

with sun exposure throughout treatment

Skin can burn more easily in the sun. Use broad-spectrum SPF 50+, cover up, and avoid strong midday sun.

reported by about 5.3% of people · from Alectinib

Lung inflammation (interstitial lung disease)

median ~2.1 months (range ~0.6-3.6)

Uncommon but serious lung inflammation, most often in the first 1-4 months, causing new cough or breathlessness. Report breathing changes promptly — the drug is held and investigated.

Call your team urgently: New or worsening breathlessness or cough — contact your team urgently.

reported by about 1.3% of people; severe in 0.4% · from Alectinib

Where this comes from

A window appears here only where a retrievable document ties it to a drug in this regimen. Where nothing could be found, the window was removed rather than estimated — so a missing time is an honest gap, not an oversight.

Alectinib (Alecensa): what to expect