Perflutren

Perflutren lipid microspheres exhibit lower acoustic impedance than blood and enhance the intrinsic backscatter of blood. These physical acoustic properties of activated DEFINITY RT provide contrast enhancement of the left ventricular chamber and aid delineation of the left ventricular endocardial border during echocardiography.

• DEFINITY RT is indicated, after activation, for use in adult and pediatric patients with suboptimal echocardiograms to opacify the left ventricular chamber and to improve the delineation of the left ventricular endocardial border. DEFINITY RT is an ultrasound contrast agent indicated, after activation, for use in adult and pediatric patients with suboptimal echocardiograms to opacify the left ventricular chamber and to improve the delineation of the left ventricular endocardial border.

• DEFINTY RT is contraindicated in patients with known or suspected hypersensitivity to Perflutren lipid microsphere or its components, such as polyethylene glycol (PEG) [see Warnings and Precautions (5.2) and Description (11) ].contraindicated

Adult Patients Bolus: 10 microL/kg intravenously over 30 seconds to 60 seconds followed by a 10 mL flush of 0.9% Sodium Chloride Injection. Infusion: 1.3 mL added to 50 mL of 0.9% Sodium Chloride Injection intravenously starting at 4 mL/minute, titrating as necessary, not to exceed 10 mL/minutes. The maximum dose is two bolus doses 30 minute apart or one single infusion. ( 2.2 ) Pediatric Patients Bolus: 3 microL/kg over 30 seconds to 60 seconds by intravenous bolus injection followed by a 5 mL flush of 0.9% Sodium Chloride Injection. The maximum dose is two bolus doses 30 minute apart. ( 2.3 ) See Full Prescribing Information for imaging instructions and preparation ( 2.4 , 2.5 ). 2.1 Important Preparation and Administration Instructions There are two formulations, DEFINITY and DEFINITY RT, that have differences in preparation and storage. Ensure of the correct product when following the directions for preparation and storage. DEFINITY RT must be activated using the VIALMIX RFID device and diluted before administration according to the instructions outlined below [see Dosage and Administration (2.5) ] . DEFINITY RT is for intravenous use only and must not be administered by intra-arterial injection [see Warnings and Precautions (5.3) ] . For adult patients, DEFINITY RT can be administered by either an intravenous bolus or infusion. The maximum dose is either two bolus doses or one single infusion. Do not administer the bolus and infusion dosing in combination or in sequence [see Dosage and Administration (2.2) ] .

Hypersensitivity Reactions: Serious acute hypersensitivity reactions have occurred. Always have cardiopulmonary resuscitation personnel and equipment readily available prior to DEFINITY RT administration and monitor all patients for acute reactions. ( 5.2 ) Pain Episodes in Patients with Sickle Cell Disease: Discontinue DEFINITY RT for new or worsening pain. ( 5.5 ) 5.1 Serious Cardiopulmonary Reactions Serious cardiopulmonary reactions including fatalities have occurred uncommonly during or shortly following perflutren-containing microsphere administration, typically within 30 minutes of administration. The risk for these 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). Always have cardiopulmonary resuscitation personnel and equipment readily available prior to DEFINITY RT administration and monitor all patients for acute reactions. The reported reactions include: 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, loss of consciousness, and convulsions [see Adverse Reactions (6.2) ] .

The following serious adverse reactions are described elsewhere in the labeling: Serious Cardiopulmonary Reactions [see Warnings and Precautions (5.1) ] Hypersensitivity Reactions [see Warnings and Precautions (5.2) ] Pain Episodes in Patients with Sickle Cell Disease [see Warnings and Precautions (5.5) ] The most common adverse reactions (≥0.5%) are headache, back/renal pain, flushing, nausea, chest pain, injection site reactions, and dizziness. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Lantheus Medical Imaging, Inc. at 1-800-362-2668 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. Adverse Reactions in Adults Safety of DEFINITY RT was evaluated in a total of 1,716 adult subjects who received DEFINITY, another formulation of perflutren lipid microspheres, in pre-market clinical trials. In this group, 1,063 (62%) were male and 653 (38%) were female, 1,328 (77%) were White, 258 (15%) were Black or African American, 74 (4%) were Hispanic, and 56 (3%) were classified as other racial or ethnic groups. The mean age was 56 years (range 18 to 93). Among the 1,716 subjects, 19 (1.1%) suffered serious cardiopulmonary adverse reactions.

8.1 Pregnancy Risk Summary Available data from case reports with DEFINITY RT use in pregnant women have not identified a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. DEFINITY RT has a very short half-life; therefore, administration of DEFINITY RT to a pregnant woman is not expected to result in clinically relevant fetal exposure. No adverse developmental outcomes were observed in animal reproduction studies with administration of activated DEFINITY, another formulation of perflutren lipid microspheres, in pregnant rats and rabbits during organogenesis at doses up to 8 and 16 times, respectively, the maximum human dose based on body surface area (see Data ) . All pregnancies have a background risk of birth defects, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Data Animal Data DEFINITY was administered intravenously to rats at doses of 0.1mL/kg, 0.3 mL/kg, and 1 mL/kg (approximately 0.8, 2.4, and 8 times the recommended maximum human dose based on body surface area); DEFINITY doses were administered daily from day 6 to day 17 of gestation.

Metabolism

Human pharmacokinetics information is not available for the intact or degassed lipid microspheres. The pharmacokinetics of perflutren gas was evaluated in healthy subjects (n=8) after the intravenous administration of activated DEFINITY at 50 microL/kg (5 times the recommended dose).

• Dec 31, 1997NDANDA020899Ge Healthcare
• Jul 31, 2001NDANDA021064Lantheus Medcl

1. 1Back Pain2,42942%
2. 2Dyspnoea80014%
3. 3Muscle Spasms75713%
4. 4Pain In Extremity5008.6%
5. 5Flushing4167.2%
6. 6Chest Pain4117.1%
7. 7Headache3876.7%
8. 8Dizziness3415.9%
9. 9Urticaria3055.3%
10. 10Neck Pain3045.2%
11. 11Nausea2824.9%
12. 12Arthralgia2434.2%
13. 13Pruritus2163.7%
14. 14Erythema2133.7%
15. 15Blood Pressure Increased2043.5%

The 10 most recently updated of 170 ClinicalTrials.gov registrations naming Perflutren as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• Microvasculature Ultrasound Super-resolution in Transplant Delayed Graft Function
  Not yet recruiting · Observational · 40 enrolled · Roderick Tan
  NCT07645599updated 2026-06-12
• Translation of Acoustic Angiography: Contrast Enhanced Super Resolution (CESR) Imaging
  Recruiting · Phase 2 · Interventional · 40 enrolled · UNC Lineberger Comprehensive Cancer Center
  NCT07225114updated 2026-06-08
• Multiparametric Ultrasound for the Diagnosis of Clinically Significant Prostate Cancer
  Not yet recruiting · Phase 3 · Interventional · 300 enrolled · Thomas Jefferson University
  NCT06024772updated 2026-06-05
• Periprosthetic Joint Infection Bubble Study
  Not yet recruiting · Phase 2 · Interventional · 100 enrolled · Thomas Jefferson University
  NCT07599865updated 2026-05-20
• Sonobiopsy for Noninvasive and Sensitive Detection of Glioblastoma
  Recruiting · Interventional · 40 enrolled · Washington University School of Medicine
  NCT05281731updated 2026-05-14
• Pancreas Ultrasound Imaging in type1 Diabetes
  Recruiting · Observational · 50 enrolled · University of Colorado, Denver
  NCT05482321updated 2026-05-06
• Head Positioning After Retina Detachment Repair
  Recruiting · Interventional · 20 enrolled · University of Kansas Medical Center
  NCT03714503updated 2026-05-05
• Peripheral Blood Flow Responses to Electromagnetic Energy
  Recruiting · Interventional · 40 enrolled · University of Alabama at Birmingham
  NCT02370199updated 2026-05-01
• Red Light Treatment in Peripheral Artery Disease
  Recruiting · Interventional · 40 enrolled · University of Alabama at Birmingham
  NCT03203239updated 2026-05-01
• tSCI Contrast Enhanced Ultrasound Study
  Completed · Phase 4 · Interventional · 27 enrolled · University of Washington
  NCT04056988updated 2026-04-29

Frequently asked questions

How does Perflutren work?

Perflutren lipid microspheres exhibit lower acoustic impedance than blood and enhance the intrinsic backscatter of blood. These physical acoustic properties of activated DEFINITY RT provide contrast enhancement of the left ventricular chamber and aid delineation of the left ventricular endocardial border during echocardiography.

What is Perflutren used for?

According to FDA labeling, Perflutren carries indications including: DEFINITY RT is indicated, after activation, for use in adult and pediatric patients with suboptimal echocardiograms to opacify the left ventricular chamber and to improve the delineation of the left ventricular endocardial border. DEFINITY RT is an ultrasound contrast agent indicated, after activation, for use in adult and pediatric patients with suboptimal echocardiograms to opacify the left ventricular chamber and to improve the delineation of the left ventricular endocardial border.. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Perflutren?

Perflutren is classified as Contrast Agent for Ultrasound Imaging, Ultrasound Contrast Activity, Unknown Physiological Effect.

What are the contraindications for Perflutren?

Perflutren labeling lists contraindications including: DEFINTY RT is contraindicated in patients with known or suspected hypersensitivity to Perflutren lipid microsphere or its components, such as polyethylene glycol (PEG) [see Warnings and Precautions (5.2) and Description (11) ].. Always consult the full prescribing information and a clinician.