Medical Editor: John P. Cunha, DO, FACOEP Last updated on RxList: 11/30/2021
Definity Side Effects Center

What Is Definity?

Definity (perflutren lipid microsphere) Injectable Suspension is a contrast agent used to brighten and clarify images of the heart during echocardiograms.

What Are Side Effects of Definity?

Common side effects of Definity include:

Dosage for Definity?

The recommended dose of Definity is 10 microliters if given via bolus, and 1.3mL if given via infusion. Definity must be administered under a doctor's supervision.

What Drugs, Substances, or Supplements Interact with Definity?

Other drugs may interact with Definity. Tell your doctor all medications you take. Before taking Definity tell your doctor if you have heart or lung conditions. If you are pregnant only use Definity if clearly needed.

Definity During Pregnancy and Breastfeeding

Exercise caution if taking Definity while breastfeeding.

Additional Information

Our Definity (perflutren lipid microsphere) Injectable Suspension Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


In the U.S., 1 in every 4 deaths is caused by heart disease. See Answer
Definity Consumer Information

Get emergency medical help if you have signs of an allergic reaction: hives, skin redness, itching; warmth, redness, numbness, or tingly feeling; wheezing, trouble breathing, tightness in your chest or throat; swelling of your face, lips, tongue, or throat.

In rare cases, serious or fatal reactions may occur during the injection or shortly afterward. Tell your caregivers right away if you have:

  • a light-headed feeling, like you might pass out;
  • severe dizziness, or a cold sweat;
  • chest pain, wheezing, trouble breathing;
  • fast or slow heartbeats;
  • severe headache, blurred vision, pounding in your neck or ears, anxiety, confusion; or
  • slow heart rate, weak pulse, fainting, weak or shallow breathing.

You may be more likely to have a serious reaction if you have severe or uncontrolled heart problems (congestive heart failure, a recent heart attack, serious heart rhythm disorder).

Common side effects may include:

  • headache, dizziness;
  • flushing (warmth, redness, or tingly feeling);
  • nausea;
  • chest pain;
  • pain in your side or lower back; or
  • pain, swelling, or irritation where the injection was given.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Read the entire detailed patient monograph for Definity (Perflutren Lipid Microsphere)


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Definity Professional Information


The following serious adverse reactions are described elsewhere in the labeling:

  • Serious Cardiopulmonary Reactions [see WARNINGS AND PRECAUTIONS]
  • Hypersensitivity Reactions [see WARNINGS AND PRECAUTIONS]

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.

A total of 1716 subjects were evaluated in pre-market clinical trials of activated DEFINITY. In this group, 1063 (61.9%) were male and 653 (38.1%) were female, 1328 (77.4%) were White, 258 (15.0%) were Black, 74 (4.3%) were Hispanic, and 56 (3.3%) were classified as other racial or ethnic groups. The mean age was 56.1 years (range 18 to 93). Of these, 144 (8.4%) had at least one adverse reaction (Table 1). There were 26 serious adverse events and 15 (0.9%) subjects discontinued because of an adverse event.

Serious Adverse Reactions

Among the 1716 study patients, 19 (1.1%) suffered serious cardiopulmonary adverse reactions.

For all adverse reactions, the overall incidence of adverse experiences was similar for the <65 year age group and the > 65 year age group, similar in males and in females, similar among all racial or ethnic groups, and similar for bolus and infusion dosing. Table 1 summarizes the most common adverse reactions.

Table 1 New-Onset Adverse Reactions Occurring in ≥0.5% of All DEFINITY-Treated Subjects

Total Number of Adverse Reactions269
Total Number of Subjects with an Adverse Reaction144(8.4%)
Body system
  Preferred termn(%)
Application Site Disorders11(0.6)
  Injection Site Reactions11(0.6)
Body as a Whole41(2.4)
  Back/renal pain20(1.2)
  Chest pain13(0.8)
Central and peripheral nervous system disorder54(3.1)
Gastrointestinal system31(1.8)
Vascular (extracardiac) disorders19(1.1)
N=Sample size 1716 subjects who received activated DEFINITY
n=Number of subjects reporting at least one Adverse Reaction

Other adverse reactions that occurred in ≤0.5% of the activated DEFINITY-dosed subjects were:

Body as a Whole: Fatigue, fever, hot flushes, pain, rigors, and syncope

Cardiovascular: Abnormal ECGs, bradycardia, tachycardia, palpitation, hypertension and hypotension

Digestive: Dyspepsia, dry mouth, tongue disorder, toothache, abdominal pain, diarrhea and vomiting

Hematology: Granulocytosis, leukocytosis, leukopenia, and eosinophilia

Musculoskeletal: Arthralgia

Nervous System: Leg cramps, hypertonia, vertigo and paresthesia

Platelet, Bleeding, and Clotting: Hematoma

Respiratory: Coughing, hypoxia, pharyngitis, rhinitis and dyspnea

Special Senses: Decreased hearing, conjunctivitis, abnormal vision and taste perversion

Skin: Pruritus, rash, erythematous rash, urticaria, increased sweating, and dry skin

Urinary: Albuminuria

Postmarketing Experience

In a prospective, multicenter, open-label registry of 1053 patients receiving DEFINITY in routine clinical practice, heart rate, respiratory rate, and pulse oximetry were monitored for 30 minutes after DEFINITY administration. No deaths or serious adverse reactions were reported, suggesting that these reactions are unlikely to occur at a rate of more than 0.3% when DEFINITY is used according to recommendations.

The following adverse reactions have been identified during the post-marketing use of perflutren-containing microsphere products. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Fatal cardiopulmonary and hypersensitivity reactions and other serious but non-fatal adverse reactions were uncommonly reported. These reactions typically occurred within 30 minutes of DEFINITY administration. These serious reactions may be increased among patients with unstable cardiopulmonary conditions (acute myocardial infarction, acute coronary artery syndromes, worsening or unstable congestive heart failure, or serious ventricular arrhythmias [see WARNINGS AND PRECAUTIONS].

Reported reactions included:


Fatal cardiac or respiratory arrest, shock, syncope, symptomatic arrhythmias (atrial fibrillation, tachycardia, bradycardia, supraventricular tachycardia, ventricular fibrillation, ventricular tachycardia), hypertension, hypotension, dyspnea, hypoxia, chest pain, respiratory distress, stridor, wheezing.


Anaphylactic reaction, anaphylactic shock, bronchospasm, throat tightness, angioedema, edema (pharyngeal, palatal, mouth, peripheral, localized), swelling (face, eye, lip, tongue, upper airway), facial hypoesthesia, rash, urticaria, pruritus, flushing, erythema.


Coma, loss of consciousness, convulsion, seizure, transient ischemic attack, agitation, tremor, vision blurred, dizziness, headache, fatigue.

Read the entire FDA prescribing information for Definity (Perflutren Lipid Microsphere)


Heart Disease: Symptoms, Signs, and Causes See Slideshow

© Definity Patient Information is supplied by Cerner Multum, Inc. and Definity Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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