What the label lists and what reports show
Alectinib side effects
Alectinib's FDA label: “The most common adverse reactions (incidence ≥20%) were hepatotoxicity, constipation, fatigue, myalgia, edema, rash and cough.” FAERS holds 7,249 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is fatigue (518 reports).
- No generic listed
Check it at the source: the alectinib FDA label on DailyMed (effective August 21, 2026, Genentech, Inc.); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of ALECENSA?ALECENSA may cause serious side effects, including: See " What is the most important information I should know about ALECENSA? " The most common side effects of ALECENSA include: constipation tiredness swelling in your hands, feet, ankles, face and eyelids rash cough These are not all of the possible side effects of ALECENSA. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Source: FDA drug label, NDA208434 (Hoffmann-La Roche), as published by Genentech, Inc., effective August 21, 2026 (SPL set 42c49deb-713b-427a-9670-08af08adcffb), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsThe most common adverse reactions (incidence ≥20%) were hepatotoxicity, constipation, fatigue, myalgia, edema, rash and cough.
Table 4: Adverse Reactions (≥ 10%) in Patients Treated with ALECENSA in ALINA
| Reaction | All Grades (%) | Grades 3-4 (%) | All Grades (%) | Grades 3-4 (%) |
|---|---|---|---|---|
| Hepatotoxicity Includes increased alanine aminotransferase, increased aspartate… | 61 | 4.7 All events are Grade 3. | 13 | 0 |
| Constipation | 42 | 0.8 | 25 | 0.8 |
| Abdominal pain Includes abdominal discomfort, abdominal pain, lower abdominal pain, upper… | 13 | 0 | 10 | 1.7 |
| Diarrhea Includes colitis and diarrhea. | 13 | 0.8 | 9 | 1.7 |
| Myalgia Includes muscle fatigue, muscular weakness, musculoskeletal chest pain,… | 34 | 0.8 | 1.7 | 0 |
| COVID-19 | 29 | 0 | 0.8 | 0 |
| Fatigue Includes asthenia and fatigue. | 25 | 0.8 | 28 | 4.2 |
| Edema Includes edema, face edema, localized edema, peripheral edema, face swelling and… | 16 | 0 | 1.7 | 0 |
| Rash Includes acneiform dermatitis, bullous dermatitis, drug eruption, eczema, rash,… | 23 | 1.6 | 10 | 0 |
| Cough Includes cough and productive cough. | 20 | 0.8 | 3.3 | 0 |
| Dyspnea Includes dyspnea and exertional dyspnea. | 13 | 0.8 | 2.5 | 0 |
| Renal Impairment Includes azotemia, increased blood creatinine, decreased renal… | 16 | 0.8 | 9 | 0 |
| Dysgeusia Includes dysgeusia and taste disorder. | 13 | 0 | 3.3 | 0 |
| Headache | 11 | 0 | 7 | 0 |
| Increased weight | 13 | 0.8 | 0.8 | 0 |
| Bradycardia Includes bradycardia and sinus bradycardia. | 12 | 0 | 0 | 0 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following adverse reactions are discussed in greater detail in other sections of the label: Hepatotoxicity [see Warnings and Precautions (5.1) ] Interstitial Lung Disease (ILD)/Pneumonitis [see Warnings and Precautions (5.2) ] Renal Impairment [see Warnings and Precautions (5.3) ] Bradycardia [see Warnings and Precautions (5.4) ] Severe Myalgia and Creatine Phosphokinase (CPK) Elevation [see Warnings and Precautions (5.5) ] Hemolytic Anemia [see Warnings and Precautions (5.6) ] Hypertriglyceridemia Leading to Pancreatitis [see Warnings and Precautions (5.7) ] Embryo-Fetal Toxicity [see Warnings and Precautions (5.8) ] The most common adverse reactions (incidence ≥20%) were hepatotoxicity, constipation, fatigue, myalgia, edema, rash and cough. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Genentech at 1-888-835-2555 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. …
Source: FDA drug label, NDA208434 (Hoffmann-La Roche), as published by Genentech, Inc., effective August 21, 2026 (SPL set 42c49deb-713b-427a-9670-08af08adcffb), via openFDA; the full label on DailyMed
What do FAERS reports show?
7,249 reports list alectinib among the medicines taken, each a report of something that happened, not proof the medicine caused it; 935 are coded as a death and 1,280 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Reports rose sharply in 2024 (1,856, against a median of 589 a year): FAERS counts follow reporting, which news, litigation and label changes can drive, not how often a reaction happens. Of the 20 reactions below, 16 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Alectinib: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions