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Epzicom Side Effects

Generic Name: abacavir / lamivudine

Note: This page contains information about the side effects of abacavir / lamivudine. Some of the dosage forms included on this document may not apply to the brand name Epzicom.

In Summary

More frequent side effects include: hypersensitivity reaction. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to abacavir / lamivudine: oral tablet

In addition to its needed effects, some unwanted effects may be caused by abacavir / lamivudine. In the event that any of these side effects do occur, they may require medical attention.

Major Side Effects

You should check with your doctor immediately if any of these side effects occur when taking abacavir / lamivudine:

More common:
  • Abdominal or stomach pain
  • cough
  • diarrhea
  • fever
  • headache
  • nausea
  • numbness or tingling of the face, feet, or hands
  • pain in the joints
  • pain in the muscles
  • shortness of breath
  • skin rash
  • sore throat
  • swelling of the feet or lower legs
  • unusual feeling of discomfort or illness
  • unusual tiredness or weakness
  • vomiting
Incidence not known:
  • Blistering, peeling, or loosening of the skin
  • bloating
  • burning, numbness, tingling, or painful sensations
  • chest pain
  • chills
  • constipation
  • convulsions
  • dark urine
  • decreased appetite
  • diarrhea
  • difficulty with swallowing
  • dizziness
  • fast heartbeat
  • fast, shallow breathing
  • feeling of fullness
  • general feeling of discomfort
  • hives or welts, itching
  • indigestion
  • light-colored stools
  • loss of appetite
  • loss of bladder control
  • muscle cramping
  • muscle spasm or jerking of all extremities
  • pains in the stomach, side, or abdomen, possibly radiating to the back
  • pale skin
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • red, irritated eyes
  • redness of the skin
  • red skin lesions, often with a purple center
  • sleepiness
  • sores, ulcers, or white spots on the lips or in the mouth
  • sudden loss of consciousness
  • swollen, painful, or tender lymph glands in the neck, armpit, or groin
  • tightness in the chest
  • troubled breathing with exertion
  • unsteadiness or awkwardness
  • unusual bleeding or bruising
  • upper right abdominal or stomach pain
  • weakness in the arms, hands, legs, or feet
  • yellow eyes and skin

Minor Side Effects

Some of the side effects that can occur with abacavir / lamivudine may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common:
  • Abnormal dreams
  • burning feeling in the chest or stomach
  • fear or nervousness
  • feeling of constant movement of self or surroundings
  • lightheadedness
  • sensation of spinning
  • severe and throbbing headache
  • stomach upset
  • tenderness in the stomach area
  • trouble sleeping
Incidence not known:
  • Abnormal breathing sounds
  • blurred vision
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • dry mouth
  • flushed, dry skin
  • fruit-like breath odor
  • gaining weight around your neck, upper back, breast, face, or waist
  • hair loss
  • increased hunger
  • increased thirst
  • increased urination
  • muscle weakness
  • sweating
  • swelling or inflammation of the mouth
  • thinning of the hair
  • unexplained weight loss

For Healthcare Professionals

Applies to abacavir / lamivudine: oral tablet


In 1 study, once- or twice-daily abacavir was used in combination with lamivudine and efavirenz. Patients receiving once-daily abacavir had a significantly higher incidence of severe drug hypersensitivity reactions and severe diarrhea than patients on the twice-daily regimen.

Many of the side effects listed occurred commonly in patients with abacavir hypersensitivity (e.g., nausea, vomiting, diarrhea, fever, lethargy, rash).[Ref]


Serious and sometimes fatal hypersensitivity reactions have been reported with abacavir. Such reactions have included multi-organ failure and anaphylaxis and usually occurred within the first 6 weeks of abacavir therapy (median onset: 9 to 11 days); however, abacavir hypersensitivity reactions have occurred any time during therapy.

Patients with the human leukocyte antigen subtype B*5701 (HLA-B*5701) allele are at higher risk of abacavir hypersensitivity reactions; however, such reactions have occurred in patients without the HLA-B*5701 allele. Abacavir hypersensitivity was reported in about 8% of patients in 9 clinical trials with abacavir-containing products where patients were not screened for the HLA-B*5701 allele; incidence of suspected abacavir hypersensitivity reactions was 1% in clinical trials where HLA-B*5701 carriers were excluded.

Abacavir hypersensitivity reactions have been characterized by at least 2 of the following key signs/symptoms: (1) fever; (2) rash; (3) gastrointestinal symptoms (including nausea, vomiting, diarrhea, abdominal pain); (4) constitutional symptoms (including generalized malaise, fatigue, achiness); (5) respiratory symptoms (including dyspnea, cough, pharyngitis). Almost all reactions have included fever and/or rash (usually maculopapular or urticarial); however, reactions also reported without fever or rash. Signs/symptoms reported in at least 10% of patients with hypersensitivity reaction have included rash, nausea, vomiting, diarrhea, abdominal pain, dyspnea, cough, fever, fatigue/lethargy, malaise, headache, elevated liver function tests, and myalgia. Other signs/symptoms of hypersensitivity have included mouth ulceration, sore throat, adult respiratory distress syndrome, respiratory failure, edema, lymphadenopathy, hypotension, conjunctivitis, anaphylaxis, paresthesia, lymphopenia, hepatitis, liver failure, myolysis, arthralgia, elevated creatine phosphokinase, elevated creatinine, renal failure, abnormal chest x-ray findings (mainly infiltrates, which were localized), and death.

Symptoms of abacavir hypersensitivity reaction worsened with continued therapy and generally resolved when abacavir was discontinued. Restarting abacavir after a hypersensitivity reaction has resulted in more severe symptoms within hours and included life-threatening hypotension and death. Rarely, life-threatening reactions have occurred within hours after restarting abacavir in patients who stopped it for reasons other than symptoms of hypersensitivity (or who stopped it with only 1 key symptom of hypersensitivity).[Ref]

Abacavir and lamivudine:
-Common (1% to 10%): Drug hypersensitivity
-Postmarketing reports: Sensitization reactions (including anaphylaxis)

-Common (1% to 10%): Hypersensitivity reactions (including fever, rash [maculopapular, urticarial], nausea, vomiting, diarrhea, abdominal pain, pharyngitis, malaise, fatigue, achiness, dyspnea, cough, lethargy, headache, myalgia, arthralgia, myolysis, edema, abnormal chest x-ray findings [mainly localized infiltrates], paresthesia, anaphylaxis, hepatitis, liver failure, renal failure, hypotension, sore throat, adult respiratory distress syndrome, respiratory failure, death, lymphadenopathy, mucous membrane lesions [conjunctivitis, mouth ulceration], erythema multiforme, elevated liver function tests, elevated creatine phosphokinase, elevated creatinine, lymphopenia)

-Frequency not reported: Anaphylactoid reactions[Ref]


Abacavir and lamivudine:
-Common (1% to 10%): Elevated ALT, elevated AST
-Uncommon (0.1% to 1%): Abnormal bilirubin
-Frequency not reported: Severe hepatomegaly with steatosis
-Postmarketing reports: Hepatic steatosis, posttreatment exacerbation of hepatitis B

-Frequency not reported: Liver function test abnormalities, elevated GGT

-Uncommon (0.1% to 1%): Transient elevations in liver enzymes (AST, ALT)
-Rare (less than 0.1%): Hepatitis
-Frequency not reported: Elevated bilirubin, elevated hepatic enzymes, hepatic decompensation, severe acute exacerbations of hepatitis[Ref]

Lactic acidosis and severe hepatomegaly with steatosis (including fatal cases) have been reported with the use of nucleoside analogs.

Elevated GGT was observed in the expanded access program for abacavir.

Hepatic decompensation (some fatal) has been reported in patients coinfected with HIV-1 and hepatitis C virus receiving combination antiretroviral therapy for HIV-1 and interferon alfa with or without ribavirin.

Severe acute exacerbations of hepatitis have been reported in patients with hepatitis B after discontinuation of lamivudine.[Ref]


Abacavir and lamivudine:
-Common (1% to 10%): Nausea, diarrhea, abdominal pain/gastritis, abnormal amylase
-Postmarketing reports: Stomatitis

-Common (1% to 10%): Nausea, vomiting, diarrhea
-Postmarketing reports: Pancreatitis (rare)

-Common (1% to 10%): Nausea, vomiting, abdominal pain/cramps, diarrhea
-Frequency not reported: Elevated lipase
-Postmarketing reports: Elevated serum amylase (rare), pancreatitis (rare)[Ref]

Pancreatitis was observed in the expanded access program for abacavir.[Ref]


Suspected Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) have been reported in patients using abacavir primarily in combination with agents known to be associated with SJS and TEN, respectively.

Cases of erythema multiforme, SJS, or TEN have been reported very rarely when abacavir hypersensitivity could not be ruled out.[Ref]

Abacavir and lamivudine:
-Common (1% to 10%): Rash
-Postmarketing reports: Alopecia, erythema multiforme, Stevens-Johnson syndrome, urticaria

-Frequency not reported: Sweet's syndrome
-Postmarketing reports: Rash without systemic symptoms (common), erythema multiforme (very rare), Stevens-Johnson syndrome (very rare), toxic epidermal necrolysis (very rare)

-Common (1% to 10%): Rash
-Rare (less than 0.1%): Angioedema
-Frequency not reported: Pruritus, urticaria
-Postmarketing reports: Alopecia (common)[Ref]


Abacavir and lamivudine:
-Common (1% to 10%): Abnormal absolute neutrophils
-Uncommon (0.1% to 1%): Abnormal hemoglobin, abnormal platelets, abnormal WBC
-Postmarketing reports: Aplastic anemia, anemia (including pure red cell aplasia and severe anemias progressing on therapy), lymphadenopathy, splenomegaly

-Frequency not reported: Anemia, neutropenia, agranulocytosis

-Uncommon (0.1% to 1%): Thrombocytopenia, neutropenia, anemia
-Postmarketing reports: Pure red cell aplasia (very rare)[Ref]

Agranulocytosis has been reported after the addition of abacavir to a multi-drug regimen.

Occasionally, neutropenia and anemia reported with lamivudine were severe.[Ref]

Nervous system

Abacavir and lamivudine:
-Common (1% to 10%): Headache/migraine, dizziness/vertigo
-Postmarketing reports: Peripheral neuropathy, paresthesia, seizures

-Common (1% to 10%): Headache

-Common (1% to 10%): Headache
-Postmarketing reports: Paresthesia (very rare), peripheral neuropathy (very rare)[Ref]


The emergence of lamivudine-resistant HBV has been reported in HIV-1/HBV-coinfected patients using lamivudine-containing antiretroviral regimens.[Ref]

Abacavir and lamivudine:
-Common (1% to 10%): Fatigue/malaise, pyrexia
-Postmarketing reports: Weakness

-Common (1% to 10%): Fever, lethargy, fatigue

-Common (1% to 10%): Fatigue, malaise, fever
-Frequency not reported: Drug-resistant hepatitis B virus (HBV)[Ref]


Abacavir and lamivudine:
-Common (1% to 10%): Insomnia, depression/depressed mood, abnormal dreams, anxiety

-Common (1% to 10%): Insomnia[Ref]


Lactic acidosis and severe hepatomegaly with steatosis (including fatal cases) have been reported with the use of nucleoside analogs.

Redistribution/accumulation of body fat has been reported with antiretroviral therapy; causality has not been established.[Ref]

Abacavir and lamivudine:
-Common (1% to 10%): Abnormal triglycerides
-Uncommon (0.1% to 1%): Abnormal alkaline phosphatase, abnormal glucose, abnormal sodium
-Frequency not reported: Lactic acidosis
-Postmarketing reports: Hyperglycemia, redistribution/accumulation of body fat

-Common (1% to 10%): Anorexia
-Frequency not reported: Elevated blood glucose, elevated triglycerides
-Postmarketing reports: Hyperlactatemia (common), lactic acidosis (rare)

-Postmarketing reports: Hyperlactatemia (common), lactic acidosis (rare)

Combination antiretroviral therapy:
-Frequency not reported: Redistribution/accumulation of body fat (including central obesity, dorsocervical fat enlargement, peripheral wasting, facial wasting, breast enlargement, "cushingoid appearance"), metabolic abnormalities (e.g., hypertriglyceridemia, hypercholesterolemia, insulin resistance, hyperglycemia, hyperlactatemia)[Ref]


Abacavir and lamivudine:
-Uncommon (0.1% to 1%): Abnormal creatine phosphokinase (CPK)
-Postmarketing reports: Muscle weakness, CPK elevation, rhabdomyolysis

-Frequency not reported: Elevated CPK

-Postmarketing reports: Arthralgia (common), muscle disorders (common), rhabdomyolysis (rare)

Combination antiretroviral therapy:
-Frequency not reported: Osteonecrosis[Ref]


-Postmarketing reports: Myocardial infarction (MI)

An observational study investigating the rate of MI in patients on combination antiretroviral therapy showed an increased risk of MI with the use of abacavir within the previous 6 months. A sponsor-conducted pooled analysis of clinical trials showed no excess risk of MI in abacavir-treated patients as compared with control subjects. Overall, available data from the observational cohort and from clinical trials were inconclusive.


Frequency not reported: Immune reconstitution/reactivation syndrome, autoimmune disorders in the setting of immune reconstitution (e.g., Graves' disease, polymyositis, Guillain-Barre syndrome)


Abacavir and lamivudine:
-Uncommon (0.1% to 1%): Abnormal creatinine[Ref]


Abacavir and lamivudine:
-Postmarketing reports: Abnormal breath sounds/wheezing

-Common (1% to 10%): Cough, nasal symptoms[Ref]


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2. "Product Information. Epzicom (abacavir-lamivudine)." GlaxoSmithKline, Research Triangle Park, NC.

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

4. Eron J Jr, Yeni P, Gathe J Jr, et al. "The KLEAN study of fosamprenavir-ritonavir versus lopinavir-ritonavir, each in combination with abacavir-lamivudine, for initial treatment of HIV infection over 48 weeks: a randomised non-inferiority trial." Lancet 368 (2006): 476-82

5. Panel on Antiretroviral Guidelines for Adults and Adolescents "Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. Department of Health and Human Services. Available from: URL:" (4/8/2015):

6. Hetherington S, McGuirk S, Powell G, et al. "Hypersensitivity reactions during therapy with the nucleoside reverse transcriptase inhibitor abacavir." Clin Ther 23 (2001): 1603-14

7. Loeliger AE, Steel H, McGuirk S, Powell WS, Hetherington SV "The abacavir hypersensitivity reaction and interruptions in therapy." Aids 15 (2001): 1325

8. Piacenti FJ "An update and review of antiretroviral therapy." Pharmacotherapy 26 (2006): 1111-33

9. Toerner JG, Cvetkovich T "Kawasaki-like Syndrome: Abacavir Hypersensitivity?" Clin Infect Dis 34 (2002): 131-2

10. Cutrell AG, Hernandez JE, Fleming JW, et al. "Updated clinical risk factor analysis of suspected hypersensitivity reactions to abacavir." Ann Pharmacother 38 (2004): 2171-2

11. Del Giudice P, Vandenbos F, Perrin C, Bernard E, Marq L, Dellamonica P "Sweet's syndrome following abacavir therapy." J Am Acad Dermatol 51 (2004): 474-5

12. Sankatsing SU, Prins JM "Agranulocytosis and fever seven weeks after starting abacavir." AIDS 15 (2001): 2464-5

Not all side effects for Epzicom may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

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