Note: This document contains side effect information about dalfopristin / quinupristin. Some dosage forms listed on this page may not apply to the brand name Synercid.

Summary

Common side effects of Synercid include: infusion site reaction, inflammation at injection site, pain at injection site, and swelling at injection site. Other side effects include: arthralgia, and myalgia. Continue reading for a comprehensive list of adverse effects.

Applies to dalfopristin / quinupristin: parenteral powder for iv infusion.

Side effects include:

Adverse effects at IV infusion site (pain, burning, inflammation, edema), GI effects (nausea, vomiting, diarrhea, anorexia), arthralgia and myalgia, hyperbilirubinemia, headache, thrombophlebitis, pain, asthenia, rash, pruritus.

For Healthcare Professionals

Applies to dalfopristin / quinupristin: intravenous powder for injection.

General

In all 5 comparative studies, patients discontinued therapy with dalfopristin-quinupristin as compared to comparator for the following reasons: venous adverse events (9.2% versus 2% comparator), rash (1% versus 0.5% comparator), nausea (0.9% versus 0.6% comparator), vomiting (0.5% versus 0.5% comparator), pain (0.5% versus 0% comparator), and pruritus (0.5% versus 0.3% comparator).

In the 2 comparative studies for complicated skin and skin structure infections (cSSSI), the side effect profile observed differed significantly from the profile observed in the other comparative studies. In these 2 comparative cSSSI studies, patients discontinued therapy with dalfopristin-quinupristin as compared to comparator for the following reasons: venous adverse events (12% versus 2% comparator), rash (2% versus 0.9% comparator), nausea (1.1% versus 0% comparator), vomiting (0.9% versus 0% comparator), pain (0.9% versus 0% comparator), and pruritus (0.9% versus 0.5% comparator). Venous adverse events were mainly observed in patients with peripheral infusions.

In noncomparative studies, approximately one-third of patients discontinued therapy due to side effects; however, the discontinuation rate due to side effects possibly or probably related to dalfopristin-quinupristin was about 5%. The side effects leading to therapy discontinuation included increased total bilirubin (2.7%), increased conjugated bilirubin (2.3%), treatment-related arthralgia (2.3%), and treatment-related myalgia (1.8%). High baseline total and conjugated bilirubin levels were recorded in 46.5% and 59% of patients, respectively, prior to study entry.

In a study with 93 patients, 21.5% discontinued treatment due to side effects. The most common side effects were arthralgia, myalgia, nausea, and rash.^[Ref]

Local

The manufacturer recommends flushing of the vein with 5% dextrose in water solution following each infusion of dalfopristin-quinupristin to minimize venous irritation. Consideration should be given to changing the infusion site in patients with moderate to severe venous irritation. Dalfopristin-quinupristin infusion (standard diluent volume of 250 mL) may also be further diluted (500 to 750 mL) in these patients. Venous adverse events occurred predominately in patients who had peripheral infusions; therefore, a peripherally inserted central catheter or a central venous catheter may be utilized in selected patients.^[Ref]

Local side effects have frequently included inflammation at the infusion site (all comparative studies: 42%; comparative cSSSI studies: 44.7%), pain at the infusion site (all comparative studies: 40%; comparative cSSSI studies: 38.2%), infusion site edema (all comparative studies: 17.3%; comparative cSSSI studies: 18%), and infusion site reaction (all comparative studies: 13.4%; comparative cSSSI studies: 11.6%).^[Ref]

Musculoskeletal

Musculoskeletal side effects have included arthralgia (up to 7.8%; severe: 3.3%), arthralgia and myalgia (up to 7.4%), myalgia (up to 5.1%; severe: 3.1%), elevated creatine phosphokinase (greater than 10 times ULN; 1.6%), and myasthenia (less than 1%). Bone pain and neck rigidity have been reported in less than 0.1% of patients.^[Ref]

Some cases of arthralgia and myalgia noted improvement of symptoms with a reduction in dose frequency to every 12 hours. Resolution of symptoms has been reported following discontinuation of dalfopristin-quinupristin.

One trial with 93 patients reported an incidence of 10.8% and 8.6%, respectively, for arthralgia and myalgia.

Intravenous dalfopristin-quinupristin plus minocycline were associated with myalgia and arthralgia in 36% of neutropenic cancer patients (n=56).^[Ref]

Gastrointestinal

Mild cases of pseudomembranous enterocolitis may respond to discontinuation of dalfopristin-quinupristin alone. Moderate to severe cases may require fluid replacement, electrolytes, protein supplementation, and antibiotics for treating C difficile.^[Ref]

Gastrointestinal side effects have included nausea (all comparative studies: 4.6%; comparative cSSSI studies: 4%; noncomparative studies: up to 4.9%), vomiting (all comparative studies: 2.7%; comparative cSSSI studies: 3.7%), and diarrhea (2.7%). Abdominal pain, constipation, dyspepsia, oral moniliasis, pancreatitis, pseudomembranous enterocolitis, and stomatitis have been reported in less than 1% of patients. Gastrointestinal hemorrhage (less than 0.2%), mesenteric arterial occlusion (less than 0.1%), and Clostridium difficile associated diarrhea have been reported.^[Ref]

Hepatic

Hepatic side effects have included increased conjugated bilirubin (greater than 5 times ULN; 3.1%), gamma-glutamyltransferase (greater than 10 times ULN; 1.9%), total bilirubin (greater than 5 times ULN; 0.9%), AST (greater than 10 times ULN; 0.9%), and ALT (greater than 10 times ULN; 0.4%). Irrespective of relationship to dalfopristin-quinupristin, increased total bilirubin (greater than 5 times ULN; 25%) and conjugated bilirubin (greater than 5 times ULN; 34.6%) were reported during noncomparative studies. Isolated hyperbilirubinemia (primarily conjugated bilirubin) can occur and is thought to be due to dalfopristin-quinupristin competing with bilirubin for excretion. Hepatitis and jaundice have been reported in less than 0.1% of patients.^[Ref]

High baseline total and conjugated bilirubin levels were recorded in 46.5% and 59% of patients, respectively, prior to noncomparative study entry.^[Ref]

Cardiovascular

Cardiovascular side effects have included thrombophlebitis (all comparative studies: 2.4%), thrombus or thrombophlebitis (comparative cSSSI studies: 1.7%), and hypotension (less than 0.2%). Palpitations, vasodilation, and phlebitis have been reported in less than 1% of patients. Arrhythmia, cerebral hemorrhage, cerebrovascular accident, heart arrest, pericardial effusion, pericarditis, supraventricular tachycardia, ventricular extrasystoles, and ventricular fibrillation have been reported in less than 0.1% of patients.^[Ref]

Dermatologic

Dermatologic side effects have included rash (all comparative studies: 2.5%; comparative cSSSI studies: 3.1%), pruritus (1.5%), and skin ulcer (less than 0.1%). Maculopapular rash, sweating, and urticaria have been reported in less than 1% of patients.^[Ref]

Hematologic

Hematologic side effects have included decreased hemoglobin (less than 8 g/dL; 2.6%), decreased platelets (less than 50,000/mm3; 0.6%), increased hematocrit (greater than 60%; 0.2%), increased platelets (greater than 1,000,000/mm3; 0.2%), and reversible reticulocytopenia. Coagulation disorder, hemolysis, hemolytic anemia, hypoplastic anemia, and pancytopenia have been reported in less than 0.1% of patients.^[Ref]

Metabolic

Metabolic side effects have included increased lactate dehydrogenase (greater than 5 times ULN; 2.6%), blood glucose (greater than 22.2 mmol/L; 1.3%), alkaline phosphatase (greater than 5 times ULN; 0.3%), bicarbonates (greater than 40 mmol/L; 0.3%), and potassium (greater than 6 mmol/L; 0.3%), and decreased bicarbonates (less than 10 mmol/L; 0.5%), sodium (less than 120 mmol/L; 0.5%), carbon dioxide (less than 15 mmol/L; 0.2%), and blood glucose (less than 2.2 mmol/L; 0.1%). Gout has been reported in less than 1% of patients. Acidosis, hypoglycemia, hyponatremia, and hypovolemia have been reported in less than 0.1% of patients. Alkalosis, hyperkalemia, and hyperglycemia have also been reported.^[Ref]

Nervous system

Nervous system side effects have included headache (1.6%). Confusion, dizziness, hypertonia, insomnia, leg cramps, and paresthesia have been reported in less than 1% of patients. Convulsion, dysautonomia, encephalopathy, grand mal convulsion, neuropathy, paraplegia, syncope, and tremor have been reported in less than 0.1% of patients.^[Ref]

Other

Other side effects have included pain (all comparative studies: 1.5%; comparative cSSSI studies: 3.1%) and shock (less than 0.1%). Abdominal pain, worsening of underlying illness, chest pain, fever, peripheral edema, and infection have been reported in less than 1% of patients.^[Ref]

Hypersensitivity

Hypersensitivity side effects have included allergic reaction (less than 1%) and anaphylactoid reaction (less than 0.1%). Angioedema and anaphylactic shock have been reported during postmarketing experience.^[Ref]

Respiratory

Respiratory side effects have included dyspnea and pleural effusion in less than 1% of patients. Apnea, hypoventilation, hypoxia, and respiratory distress syndrome have been reported in less than 0.1%.^[Ref]

Genitourinary

Genitourinary side effects have included hematuria and vaginitis in less than 1% of patients.^[Ref]

Psychiatric

Psychiatric side effects have included anxiety in less than 1% of patients.

Renal

Renal side effects have included elevated BUN (35.5 mmol/L or greater; 0.3%) and creatinine (440 mcmol/L or greater; 0.1%).^[Ref]