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Ado-trastuzumab emtansine Side Effects

Medically reviewed by Last updated on Oct 27, 2022.


Commonly reported side effects of ado-trastuzumab emtansine include: increased serum bilirubin, increased serum transaminases, cough, decreased platelet count, dyspnea, fatigue, fever, peripheral neuropathy, and thrombocytopenia. Other side effects include: chills. Continue reading for a comprehensive list of adverse effects.

Applies to ado-trastuzumab emtansine: intravenous powder for solution.


Intravenous route (Powder for Solution)

Do not substitute ado-trastuzumab emtansine with or for trastuzumab. Hepatotoxicity, liver failure, reductions in left ventricular ejection fraction, and death have occurred in ado-trastuzumab emtansine-treated patients. Monitor hepatic function and left ventricular function before beginning treatment and before each dose. Modify, hold, or discontinue treatment as necessary. Exposure to ado-trastuzumab emtansine during pregnancy can result in embryo-fetal harm. Advise patients of these risks and the need for effective contraception.

Serious side effects

Along with its needed effects, ado-trastuzumab emtansine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking ado-trastuzumab emtansine:

More common

  • Black, tarry stools
  • bladder pain
  • bleeding gums
  • bloating or swelling of the face, arms, hands, lower legs, or feet
  • bloody or cloudy urine
  • blurred vision
  • burning, numbness, tingling, or painful sensations
  • chills
  • cough
  • decreased urine
  • difficult or labored breathing
  • difficult, burning, or painful urination
  • dizziness
  • dry mouth
  • fever
  • frequent urge to urinate
  • headache
  • increased thirst
  • irregular heartbeat
  • loss of appetite
  • lower back or side pain
  • mood changes
  • muscle pain or cramps
  • nausea
  • nervousness
  • nosebleeds
  • numbness or tingling in the hands, feet, or lips
  • pale skin
  • pinpoint red spots on the skin
  • pounding in the ears
  • rapid weight gain
  • seizures
  • slow or fast heartbeat
  • sore throat
  • stomach pain
  • tightness in the chest
  • troubled breathing with exertion
  • ulcers, sores, or white spots in the mouth
  • unsteadiness or awkwardness
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • unusual weight gain or loss
  • vomiting
  • weakness in the arms, hands, legs, or feet

Less common

  • Chest pain
  • dilated neck veins
  • extreme tiredness or weakness
  • general feeling of discomfort or illness
  • irregular breathing
  • skin rash
  • thickening of bronchial secretions


  • Dark urine
  • general feeling of tiredness or weakness
  • light-colored stools
  • stomach bloating
  • vomiting blood
  • yellow eyes or skin

Incidence not known

  • Agitation
  • confusion
  • decreased awareness or responsiveness
  • depression
  • hostility
  • irritability
  • itching
  • joint pain, stiffness, or swelling
  • loss of consciousness
  • muscle twitching
  • severe sleepiness
  • stomach tenderness or cramps

Other side effects

Some side effects of ado-trastuzumab emtansine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Less common

  • Burning, dry, or itching eyes
  • discharge or excessive tearing
  • redness, pain, or swelling of the eye, eyelid, or inner lining of the eyelid

For Healthcare Professionals

Applies to ado-trastuzumab emtansine: intravenous powder for injection.


Common (1% to 10%): Left ventricular dysfunction, hypertension, peripheral edema[Ref]


Very common (10% or more): Rash (12%)

Common (1% to 10%): Pruritus, alopecia, nail disorder, palmar-plantar erythrodysesthesia syndrome, urticaria[Ref]


Very common (10% or more): Nausea (40%), constipation (24%), vomiting (20%), diarrhea (20%), dry mouth (16%), abdominal pain (16%), stomatitis (15%), stomatitis

Common (1% to 10%): Dyspepsia, gingival bleeding[Ref]


Very common (10% or more): Urinary tract infection (12%)[Ref]


Very common (10% or more): Hemorrhage (35%), thrombocytopenia (25%), anemia (15%), hemorrhage

Common (1% to 10%): Neutropenia, leucopenia[Ref]


Very common (10% or more): Transaminases increased (12%)

Common (1% to 10%):

Uncommon (0.1% to 1%): Hepatotoxicity, hepatic failure, nodular regenerative hyperplasia, portal hypertension

Rare (0.01% to 0.1%): Portal hypertension, hepatic failure, nodular regenerative hyperplasia[Ref]


Common (1% to 10%): Hypersensitivity[Ref]


Common (1% to 10%): Immunogenicity[Ref]


Very common (10% or more): Hypokalemia (11%)

Common (1% to 10%): Blood alkaline phosphatase increased[Ref]


Very common (10% or more): Musculoskeletal pain (36%), arthralgia (19%), myalgia (13%)[Ref]

Nervous system

Very common (10% or more): Headache (28%), peripheral neuropathy (23%), asthenia, chills

Common (1% to 10%): Dizziness, dysgeusia, memory impairment[Ref]


Common (1% to 10%): Dry eye, conjunctivitis, blurred vision, lacrimation increased[Ref]


Very common (10% or more): Fatigue (37%), pyrexia (23%), asthenia (16%), chills (10%)[Ref]


Very common (10% or more): Insomnia (12%)[Ref]


Very common (10% or more): Epistaxis (24%), cough (20%), dyspnea (13%)

Uncommon (0.1% to 1%): Pneumonitis[Ref]


Uncommon (0.1% to 1%): Injection site extravasation, infusion-related reactions[Ref]

Frequently asked questions


1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

2. Cerner Multum, Inc. "Australian Product Information." O 0

3. "Product Information. Kadcyla (ado-trastuzumab emtansine)." Genentech (2022):

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.