What the label lists and what reports show
Dacomitinib side effects
Dacomitinib's FDA label: “Most common adverse reactions (incidence >20%) are diarrhea, rash, paronychia, stomatitis, decreased appetite, dry skin, decreased weight, alopecia, cough, and pruritus.” FAERS holds 746 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 diarrhoea (119 reports).
- No generic listed
- A presentation discontinued
Check it at the source: the dacomitinib FDA label on DailyMed (effective June 23, 2026, Pfizer Laboratories Div Pfizer 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 VIZIMPRO?VIZIMPRO may cause serious side effects, including: • Lung or breathing problems. VIZIMPRO may cause severe inflammation of the lung that may lead to death. Symptoms may be similar to those symptoms from lung cancer. Tell your healthcare provider right away if you have any new or worsening lung symptoms, including trouble breathing or shortness of breath, cough, or fever. • Diarrhea. Diarrhea is common during treatment with VIZIMPRO, and can be severe and lead to death. Diarrhea can cause you to lose too much body fluid (dehydration). Your healthcare provider may tell you to start drinking more fluids or start taking your anti-diarrheal medicines. Tell your healthcare provider right away, if you have any loose stools or have stools more often than is normal for you. • Skin reactions. Skin reactions are common with VIZIMPRO and can be severe. […]
Source: FDA drug label, Pfizer Laboratories Div Pfizer Inc, effective June 23, 2026 (SPL set 4ab27d2f-e385-4e9c-b324-fa69c10b855a), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common adverse reactions (incidence >20%) are diarrhea, rash, paronychia, stomatitis, decreased appetite, dry skin, decreased weight, alopecia, cough, and pruritus.
Table 3. Adverse Reactions Occurring in ≥10% of Patients Receiving VIZIMPRO in ARCHER 1050 National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) v4.03.
| Reaction | All Grades Grades 1 through 5 are included in All Grades. % | Grades 3 and 4 % | All Grades % | Grades 3 and 4 % |
|---|---|---|---|---|
| Diarrhea One Grade 5 (fatal) event in the VIZIMPRO arm. | 87 | 8 | 56 | 0.9 |
| Stomatitis Stomatitis includes mucosal inflammation and stomatitis. | 45 | 4.4 | 19 | 0.4 |
| Nausea | 19 | 1.3 | 22 | 0.4 |
| Constipation | 13 | 0 | 14 | 0 |
| Mouth ulceration | 12 | 0 | 6 | 0 |
| Rash Rash includes dermatitis acneiform, rash, and rash maculo-papular. | 69 | 23 | 47 | 0.4 |
| Paronychia Paronychia includes nail infection, nail toxicity, onychoclasis, onycholysis,… | 64 | 8 | 21 | 1.3 |
| Dry skin Dry skin includes dry skin, xerosis. | 30 | 1.8 | 19 | 0.4 |
| Alopecia | 23 | 0.4 | 13 | 0 |
| Pruritus Pruritus includes pruritus, pruritus generalized, rash pruritic. | 21 | 0.9 | 15 | 1.3 |
| Palmar-plantar erythrodysesthesia syndrome | 15 | 0.9 | 3.1 | 0 |
| Dermatitis | 11 | 1.8 | 4 | 0.4 |
| Decreased appetite | 31 | 3.1 | 25 | 0.4 |
| Decreased weight | 26 | 2.2 | 17 | 0.4 |
| Cough | 21 | 0 | 19 | 0.4 |
| Nasal mucosal disorder Nasal mucosal disorder includes epistaxis, nasal inflammation,… | 19 | 0 | 4.9 | 0 |
| Dyspnea | 13 | 2.2 | 13 | 1.8 |
| Upper respiratory tract infection | 12 | 1.3 | 13 | 0 |
| Chest pain | 10 | 0 | 14 | 0 |
| Conjunctivitis | 19 | 0 | 4 | 0 |
| Pain in extremity | 14 | 0 | 12 | 0 |
| Musculoskeletal pain | 12 | 0.9 | 13 | 0 |
| Asthenia | 13 | 2.2 | 13 | 1.3 |
| Insomnia | 11 | 0.4 | 15 | 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 drug reactions are described elsewhere in the labeling: • Interstitial Lung Disease [see Warnings and Precautions (5.1) ] • Diarrhea [see Warnings and Precautions (5.2) ] • Dermatologic Adverse Reactions [see Warnings and Precautions (5.3) ] Most common adverse reactions (incidence >20%) are diarrhea, rash, paronychia, stomatitis, decreased appetite, dry skin, decreased weight, alopecia, cough, and pruritus. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Pfizer Inc. at 1-800-438-1985 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. The data in the Warnings and Precautions section reflect exposure to VIZIMPRO in 394 patients with first-line or previously treated NSCLC with EGFR exon 19 deletion or exon 21 L858R substitution mutations who received VIZIMPRO at the recommended dose of 45 mg once daily in 4 randomized, active-controlled trials [ARCHER 1050 (N=227), Study A7471009 (N=38), Study A7471011 (N=83), and Study A7471028 (N=16)] and one single-arm trial [Study A7471017 (N=30)]. …
Source: FDA drug label, Pfizer Laboratories Div Pfizer Inc, effective June 23, 2026 (SPL set 4ab27d2f-e385-4e9c-b324-fa69c10b855a), via openFDA; the full label on DailyMed
What do FAERS reports show?
746 reports list dacomitinib among the medicines taken, each a report of something that happened, not proof the medicine caused it; 329 are coded as a death and 212 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. Of the 22 reactions below, 12 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?
- Dacomitinib: 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