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Omega-3-acid Ethyl Esters

Class: Antilipemic Agents, Miscellaneous
VA Class: CV350
Chemical Name: EPA ethyl ester: (all-Z)-5,8,11,14,17-Eicosapentaenoic acid ethyl ester. DHA ethyl ester: (all-Z)-4,7,10,13,16,19-Docosahexaenoic acid ethyl ester.
Molecular Formula: EPA ethyl ester: C22H34O2. DHA ethyl ester: C24H36O2
CAS Number: 86227-47-6
Brands: Lovaza, Omtryg

Medically reviewed by on Oct 27, 2020. Written by ASHP.


Antilipemic agent; combination consisting predominantly of ethyl esters of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

Uses for Omega-3-acid Ethyl Esters


Adjunct to dietary therapy to reduce triglyceride concentrations in adults with severe hypertriglyceridemia (triglyceride concentration ≥500 mg/dL). Efficacy in reducing risk of pancreatitis or risk of cardiovascular morbidity or mortality in these patients not established.

Has been used as monotherapy to reduce high (200–499 mg/dL) triglyceride concentrations in adults. However, because most of these patients are expected to receive statins as initial therapy, some experts state that efficacy should be further evaluated in patients receiving concomitant statin therapy. Preliminary data indicate additive effects on reduction of triglyceride and VLDL-cholesterol concentrations when used with statins.

Treatment may result in increases in LDL- and non-HDL-cholesterol concentrations in some individuals.

Prevention of Cardiovascular Events

Marine- and plant-derived omega-3 fatty acids (i.e., EPA, DHA, α-linolenic acid) have been used for primary or secondary prevention of CHD.

ACC/AHA cholesterol guideline states that nonstatin drugs (e.g., omega-3-acid ethyl esters) do not provide acceptable atherosclerotic cardiovascular disease (ASCVD) risk reduction benefits compared to their potential for adverse effects in the routine prevention of ASCVD. May be useful as adjuncts to statin therapy in high-risk patients (e.g., patients with ASCVD, LDL-cholesterol concentrations ≥190 mg/dL, or diabetes mellitus) who have a less-than-anticipated response to statins, are unable to tolerate even a less-than-recommended intensity of a statin, or are completely intolerant to statin therapy. Select nonstatin drug based on favorable benefit-risk ratio (i.e., demonstrated benefit of ASCVD risk reduction outweighs risks of adverse effects and drug interactions) and patient preferences.

Current recommendations from ACC/AHA regarding prevention of ASCVD and lifestyle modifications to reduce cardiovascular risk are available at or [Web]

Omega-3-acid Ethyl Esters Dosage and Administration


  • Patients should be placed on a standard cholesterol-lowering diet before initiation of omega-3-acid ethyl esters therapy and should remain on this diet during treatment with the drug.


Oral Administration

Lovazais administered with meals in clinical studies. Manufacturer recommends administering Omtryg capsules with meals.

Swallow capsules whole; do not break, crush, dissolve, or chew.


Each 1- or 1.2-g capsule contains ≥900 mg of the ethyl esters of omega-3 fatty acids (approximately 465 mg from ethyl esters of EPA and 375 mg from ethyl esters of DHA).



Lovaza: 4 g daily as a single dose or in 2 equally divided doses. Discontinue if adequate response not achieved after 2 months of therapy.

Omtryg: 4.8 g daily as a single dose or in 2 equally divided doses.

Prevention of Cardiovascular Events

AHA suggests incorporating omega-3 fatty acids in diet, although benefit in reducing CHD risk or total mortality not established.

For primary prevention, AHA suggests consumption of a variety of fish (preferably fatty fish such as herring, mackerel, salmon, sardines, or tuna) at least twice weekly and inclusion of oils and foods rich in α-linolenic acid (e.g., canola/flaxseed/soybean oils, flaxseeds, English walnuts) in diet.

For secondary prevention, AHA suggests consumption of approximately 1 g of a combination of EPA and DHA daily, preferably through dietary means (i.e., consumption of fatty fish); if intake cannot be achieved with diet alone, may consider supplements, but only in consultation with a clinician.

Third Report of the National Cholesterol Education Program (NCEP) (Adult Treatment Panel [ATP] III) did not recommend specific amount of omega-3 fatty acids for daily intake but does support AHA's recommendation to include fish in diet. Higher dietary intakes (1–2 g daily) identified by ATP III as an option for secondary prevention, but more definitive clinical trials required before such high dosages can be strongly recommended for either primary or secondary prevention.

Special Populations

No special population recommendations at this time.

Cautions for Omega-3-acid Ethyl Esters


  • Known hypersensitivity (e.g., anaphylactic reaction) to omega-3-acid ethyl esters or any ingredient in the formulation.


Sensitivity Reactions

Fish Sensitivity

Obtained from the oil of several fish sources. Not known whether patients with hypersensitivity to fish and/or shellfish are at increased risk of allergic reactions; therefore, use with caution in such patients.

Anaphylactic reactions reported during postmarketing experience.

Major Toxicities

Hepatic Effects

Increases in ALT concentrations without a concurrent increase in AST concentrations reported in some patients. Monitor ALT and AST concentrations periodically during therapy in patients with hepatic impairment.

Recurrent Atrial Fibrillation or Flutter

Recurrent atrial fibrillation or flutter reported in patients with symptomatic paroxysmal or persistent atrial fibrillation receiving omega-3-acid ethyl esters. Clinical importance unknown; however, possible association between use of the drug and more frequent recurrences of symptomatic atrial fibrillation or flutter in such patients, especially within 2–3 months of initiation of therapy.

Omega-3-acid ethyl esters is not indicated for treatment of atrial fibrillation or flutter.

General Precautions

Laboratory Monitoring

Prior to initiating therapy, evaluate lipoprotein profiles to confirm the presence of persistent hypertriglyceridemia. During therapy, obtain lipoprotein profiles periodically to monitor clinical response (i.e., reduction in triglyceride concentrations) or adverse effects (i.e., excessive increases in LDL-cholesterol concentrations).

Monitor ALT and AST concentrations periodically during therapy. (See Hepatic Effects under Cautions.)

Adjunctive Measures

Prior to initiating therapy, vigorously attempt to control serum triglyceride concentrations with appropriate dietary regimens, exercise, weight reduction, and treatment of any underlying disorder that might be the cause of triglyceride abnormalities (e.g., diabetes mellitus, hypothyroidism).

If possible, discontinue or change drugs known to exacerbate hypertriglyceridemia (e.g., β-adrenergic blocking agents, thiazides, estrogens) before initiating therapy.

Prolongation of Bleeding Time

Prolongation of bleeding time observed with omega-3 fatty acids; however, such prolongation has not exceeded normal limits and was not associated with clinically important bleeding episodes. Blood testing is not required; however, monitor patients for manifestations of bleeding prior to and during therapy. (See Interactions.)

Hemorrhagic diatheses also reported.

Specific Populations


Category C.


Distributed into milk; possible effects on nursing infants unknown. Caution if used in nursing women.

Pediatric Use

Safety and efficacy not established in pediatric patients.

Geriatric Use

Experience in patients >65 years of age is limited. No substantial differences in safety and efficacy observed between patients >60 years of age and younger patients.

Hepatic Impairment

Monitor ALT and AST concentrations periodically. (See Hepatic Effects under Cautions.)

Common Adverse Effects

Eructation, dyspepsia, taste perversion.

Interactions for Omega-3-acid Ethyl Esters

Drugs Affecting Coagulation

Monitor (e.g., PT/INR) periodically during concomitant therapy. (See Prolongation of Bleeding Time under Cautions.)

Drugs Metabolized by Hepatic Microsomal Enzymes

Free forms of EPA and DHA cause modest inhibition of CYP isoenzymes 1A2, 2A6, 2C9, 2C19, 2D6, 2E1, and 3A in vitro. However, because free forms of EPA and DHA are undetectable in systemic circulation (<1 µM), clinically important interactions with drugs metabolized by the CYP enzyme system not expected to occur in humans.

Specific Drugs





Concomitant use not adequately studied

Monitor PT/INR periodically during concomitant use

Antiplatelet agents

Monitor coagulation status periodically during concomitant use

HMG-CoA reductase inhibitors (statins) (i.e., atorvastatin, rosuvastatin, simvastatin)

No effect on peak concentration or AUC of statins and their metabolites

Omega-3-acid Ethyl Esters Pharmacokinetics



EPA and DHA are absorbed systemically following oral administration as ethyl esters.


Following oral administration of Omtryg capsules under fasted conditions, peak concentration or AUC of total plasma EPA decreased by 20- or 80-fold, respectively, and peak concentration or AUC of total plasma DHA decreased by 2- or 4-fold, respectively, compared with administration under fed conditions (with a high-fat, high-calorie meal).



Oral administration of omega-3-acid ethyl esters results in substantial, dose-dependent increases in EPA content in serum phospholipids and less substantial, non-dose-dependent increases in DHA content.

Special Populations

Uptake of EPA and DHA into serum phospholipids is independent of age. EPA uptake, however, appears to be higher in women than in men.

Pharmacokinetics not studied in pediatric patients or patients with renal or hepatic impairment.





25°C (may be exposed to 15–30°C); do not freeze.


  • EPA and DHA, collectively known as marine-derived omega-3 fatty acids (n-3 fatty acids), are long-chain, polyunsaturated fatty acids (PUFAs) obtained primarily from marine sources such as fatty fish (e.g., herring, mackerel, salmon, sardines, tuna).

  • Mechanism of action not completely understood; may inhibit diacylglycerol O-acyltransferase, increase mitochondrial and peroxisomal β-oxidation in the liver, decrease lipogenesis in the liver, and increase plasma lipoprotein lipase activity.

  • May reduce synthesis of triglycerides and VLDL-cholesterol in the liver; also may inhibit esterification of other fatty acids.

Advice to Patients

  • Importance of adherence to standard cholesterol-lowering diet.

  • Risk of hypersensitivity. Advise patients to use the drug with caution if they have known hypersensitivity to fish and/or shellfish.

  • Importance of swallowing omega-3-acid ethyl esters capsules whole; do not break, crush, dissolve, or chew capsules.

  • Importance of taking Omtryg capsules with meals.

  • Importance of taking omega-3-acid ethyl esters as prescribed. If a dose is missed, take the dose as soon as it is remembered. If one day of omega-3-acid ethyl esters therapy is missed, do not double the dose.

  • Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.

  • Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses.

  • Importance of informing patients of other important precautionary information. (See Cautions.)


Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Omega-3-acid Ethyl Esters


Dosage Forms


Brand Names



Capsules, liquid-filled

1 g*



Omega-3-acid Ethyl Esters Capsules

1.2 g



AHFS DI Essentials™. © Copyright 2021, Selected Revisions November 6, 2014. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.

† Use is not currently included in the labeling approved by the US Food and Drug Administration.

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