Cefaclor Side Effects

Medically reviewed by Drugs.com. Last updated on Sep 30, 2024.

Applies to cefaclor: oral capsules, oral extended-release tablets, oral for suspension.

Side effects include:

Diarrhea, genital pruritus or vaginitis, headache, nausea, vomiting, rash.

For healthcare professionals

Applies to cefaclor: oral capsule, oral powder for reconstitution, oral tablet chewable, oral tablet extended release.

General adverse events

ER TABLETS: The most commonly reported side effects included headache, rhinitis, diarrhea, and nausea.

IR CAPSULES: The most commonly reported side effects included abdominal pain, diarrhea, morbilliform eruptions, and hypersensitivity reactions.

CR/MR TABLETS: The most commonly reported side effects included headache, diarrhea, nausea, and vaginal moniliasis.

ORAL SUSPENSION: The most commonly reported side effects included diarrhea and hypersensitivity reactions.^[Ref]

Gastrointestinal

ER TABLETS:

• Common (1% to 10%): Abdominal pain, diarrhea, nausea
• Uncommon (0.1% to 1%): Constipation, dyspepsia, flatulence, gastritis, nausea and vomiting, vomiting
• Postmarketing reports: Pseudomembranous colitis symptoms

IR CAPSULES:

• Common (1% to 10%): Diarrhea
• Rare (0.01% to 0.1%): Nausea, vomiting
• Frequency not reported: Abdominal pain, colitis, pseudomembranous colitis

CR/MR TABLETS:

• Common (1% to 10%): Abdominal pain, diarrhea, nausea
• Frequency not reported: Colitis, dyspepsia, pseudomembranous colitis, vomiting

ORAL SUSPENSION:

• Common (1% to 10%): Diarrhea, gastrointestinal symptoms
• Rare (0.01% to 0.1%): Colitis, pseudomembranous colitis, nausea, vomiting
• Frequency not reported: Abdominal pain^[Ref]

Dermatologic

ER TABLETS:

• Common (1% to 10%): Pruritus
• Uncommon (0.1% to 1%): Maculopapular rash, rash, sweating, urticaria
• Frequency not reported: Erythema multiforme
• Postmarketing reports: Face edema, Stevens-Johnson syndrome, toxic epidermal necrolysis

IR CAPSULES:

• Common (1% to 10%): Morbilliform eruption
• Very rare (less than 0.01%): Pruritus, urticaria
• Frequency not reported: Erythema multiforme, face edema, rash, Stevens-Johnson syndrome, toxic epidermal necrolysis

CR/MR TABLETS:

• Common (1% to 10%): Pruritus, rash, urticaria
• Frequency not reported: Erythema multiforme, erythema multiforme minor, face edema, morbilliform eruptions, Stevens-Johnson syndrome, toxic epidermal necrolysis

ORAL SUSPENSION:

• Common (1% to 10%): Morbilliform eruptions
• Uncommon (0.1% to 1%): Erythema multiforme, pruritus, rash, urticaria
• Rare (0.01% to 0.1%): Erythema multiforme major, Stevens-Johnson syndrome, toxic epidermal necrolysis
• Frequency not reported: Erythema multiforme minor, face edema^[Ref]

Genitourinary

ER TABLETS:

• Common (1% to 10%): Vaginal moniliasis, vaginitis
• Uncommon (0.1% to 1%): Dysmenorrhea, dysuria, leukorrhea, menstrual disorder, nocturia
• Postmarketing reports: Abnormal urinalysis, genital pruritus

IR CAPSULES:

• Frequency not reported: Abnormal urinalysis, false positive test for urinary glucose, genital pruritus, vaginal moniliasis, vaginitis

CR/MR TABLETS:

• Common (1% to 10%): Vaginal moniliasis, vaginitis
• Frequency not reported: Abnormal urinalysis, genital pruritus, hematuria, proteinuria, pyuria

ORAL SUSPENSION:

• Frequency not reported: Abnormal urinalysis, false positive test for urinary glucose, genital pruritus, hematuria, proteinuria, pyuria, vaginal moniliasis, vaginitis^[Ref]

Respiratory

ER TABLETS:

• Common (1% to 10%): Cough increased, pharyngitis, rhinitis
• Uncommon (0.1% to 1%): Asthma, bronchitis, lung disorder, respiratory disorder, sinusitis

IR CAPSULES:

• Frequency not reported: Dyspnea

CR/MR TABLETS:

• Common (1% to 10%): Epistaxis
• Frequency not reported: Dyspnea

ORAL SUSPENSION:

• Frequency not reported: Dyspnea^[Ref]

Hypersensitivity

ER TABLETS:

• Uncommon (0.1% to 1%): Serum sickness-like reaction
• Frequency not reported: Hypersensitivity reactions, severe hypersensitivity reactions
• Postmarketing reports: Allergic reaction, anaphylactoid events, anaphylaxis, angioedema

IR CAPSULES:

• Common (1% to 10%): Hypersensitivity reactions
• Uncommon (0.1% to 1%): Serum sickness-like reaction
• Frequency not reported: Anaphylactoid events, anaphylaxis, angioedema, severe hypersensitivity reactions

CR/MR TABLETS:

• Rare (0.01% to 0.1%): Serum sickness-like reaction
• Frequency not reported: Allergic reactions, anaphylactoid events, anaphylaxis, angioedema, severe hypersensitivity reactions

ORAL SUSPENSION:

• Common (1% to 10%): Hypersensitivity reactions
• Uncommon (0.1% to 1%): Serum sickness-like reactions
• Rare (0.01% to 0.1%): Anaphylaxis, angioedema
• Frequency not reported: Anaphylactoid events^[Ref]

Anaphylaxis may occur more frequently in patients with a history of penicillin allergy.

Hypersensitivity reaction symptoms may persist for several months.

Serum-sickness-like reactions were more frequently reported in pediatric patients and after a second/subsequent course of treatment; reactions have been characterized by arthritis/arthralgia, erythema multiforme, and rash with or without fever.^[Ref]

Musculoskeletal

ER TABLETS:

• Common (1% to 10%): Back pain
• Uncommon (0.1% to 1%): Arthralgia, creatine phosphokinase increased, myalgia, neck pain, somnolence
• Frequency not reported: Arthritis

IR CAPSULES:

• Frequency not reported: Arthralgia, arthritis

CR/MR TABLETS:

• Frequency not reported: Arthralgia, arthritis

ORAL SUSPENSION:

• Frequency not reported: Arthralgia, arthritis^[Ref]

Nervous system

ER TABLETS:

• Common (1% to 10%): Headache
• Uncommon (0.1% to 1%): Dizziness, somnolence, tremor
• Postmarketing reports: Hypertonia, paresthesia, reversible hyperactivity, syncope, vertigo

IR CAPSULES:

• Rare (0.01% to 0.1%): Dizziness, hypertonia, reversible hyperactivity, somnolence
• Frequency not reported: Paresthesia, seizures, syncope

CR/MR TABLETS:

• Common (1% to 10%): Headache
• Frequency not reported: Dizziness, hypertonia, paresthesia, reversible hyperactivity, seizures, somnolence, syncope

ORAL SUSPENSION:

• Rare (0.01% to 0.1%): Dizziness, hypertonia, reversible hyperactivity, somnolence
• Frequency not reported: Paresthesia, seizures, syncope^[Ref]

Hematologic

ER TABLETS:

• Uncommon (0.1% to 1%): Eosinophils increased, erythrocyte count decreased, hemoglobin decreased, lymphocytes decreased, mean cell volume (MCV) increased, neutrophils segmented decreased, platelet count decreased
• Postmarketing reports: Eosinophilia, hemolytic anemia, leukopenia, neutropenia, positive direct Coombs test, transient thrombocytopenia

IR CAPSULES:

• Rare (0.01% to 0.1%): Agranulocytosis, aplastic anemia, hemolytic anemia, reversible neutropenia (may be of clinical significance), thrombocytopenia
• Very rare (less than 0.01%): Positive Coombs test
• Frequency not reported: Eosinophilia, pancytopenia, transient leukopenia, transient lymphocytosis
• Postmarketing reports: Increased prothrombin time with/without clinical bleeding

CR/MR TABLETS:

• Frequency not reported: Agranulocytosis, aplastic anemia, eosinophilia, hemolytic anemia, increased prothrombin time with/without clinical bleeding, leukopenia, lymphadenopathy, lymphocytosis, neutropenia (may be of clinical significance), positive direct Coombs test, transient fluctuations in leukocyte count, transient thrombocytopenia

ORAL SUSPENSION:

• Uncommon (0.1% to 1%): Positive Coombs test
• Rare (0.01% to 0.1%): Agranulocytosis, aplastic anemia, hemolytic anemia, reversible neutropenia (may be of clinical significance), thrombocytosis, thrombocytopenia
• Frequency not reported: Eosinophilia, leukopenia, lymphadenopathy, pancytopenia, transient fluctuations in leukocyte count, transient lymphocytosis
• Postmarketing reports: Increased prothrombin time with/without clinical bleeding^[Ref]

Increased prothrombin time with/without clinical bleeding was reported in patients given IR capsules and warfarin concurrently.

Transient fluctuations in leukocyte count most commonly occurred in infants and young children.^[Ref]

Other

ER TABLETS:

• Uncommon (0.1% to 1%): Accidental injury, chills, ear pain, fever, malaise, otitis media, pain, surgical procedure

IR CAPSULES:

• Frequency not reported: Asthenia, fever

CR/MR TABLETS:

• Common (1% to 10%): Asthenia, pain
• Frequency not reported: Fever

ORAL SUSPENSION:

• Rare (0.01% to 0.1%): Fever
• Frequency not reported: Asthenia^[Ref]

Metabolic

ER TABLETS:

• Uncommon (0.1% to 1%): Albumin decreased, anorexia, calcium increased, phosphorus increased, potassium increased, sodium decreased/increased^[Ref]

Hepatic

ER TABLETS:

• Uncommon (0.1% to 1%): Alkaline phosphatase increased, ALT increased, GGT increased, total bilirubin increased
• Postmarketing reports: Cholestasis, liver dysfunction, transient AST elevation

IR CAPSULES:

• Rare (0.01% to 0.1%): Cholestatic jaundice, transient hepatitis
• Frequency not reported: Elevated bilirubin, elevated LDH, slight alkaline phosphatase elevations, slight ALT elevations, slight AST elevations

CR/MR TABLETS:

• Frequency not reported: Cholestasis, cholestatic jaundice, liver dysfunction, transient alkaline phosphatase elevations, transient ALT elevations, transient AST elevations, transient hepatitis

ORAL SUSPENSION:

• Rare (0.01% to 0.1%): Cholestatic jaundice, liver dysfunction, transient hepatitis
• Frequency not reported: Elevated bilirubin, elevated LDH, slight alkaline phosphatase elevations, slight ALT elevations, slight AST elevations^[Ref]

Cardiovascular

EXTENDED RELEASE (ER) TABLETS:

• Uncommon (0.1% to 1%): Chest pain, congestive heart failure, edema, palpitation, peripheral edema
• Postmarketing reports: Hypotension, limb edema, vasodilation

IMMEDIATE RELEASE (IR) CAPSULES:

• Frequency not reported: Hemorrhage, hypotension, limb edema, vasodilation

MODIFIED RELEASE (CR/MR) TABLETS:

• Frequency not reported: Limb edema, vasodilation

ORAL SUSPENSION:

• Frequency not reported: Hemorrhage, hypotension, limb edema, vasodilation^[Ref]

Psychiatric

ER TABLETS:

• Uncommon (0.1% to 1%): Anxiety, insomnia, nervousness
• Postmarketing reports: Confusion

IR CAPSULES:

• Rare (0.01% to 0.1%): Agitation, confusion, hallucinations, insomnia, nervousness

CR/MR TABLETS:

• Frequency not reported: Agitation, confusion, hallucinations, insomnia, nervousness

ORAL SUSPENSION:

• Rare (0.01% to 0.1%): Agitation, confusion, hallucinations, insomnia, nervousness^[Ref]

Renal

ER TABLETS:

• Uncommon (0.1% to 1%): Blood urea nitrogen (BUN) increased, creatinine increased
• Postmarketing reports: Reversible interstitial nephritis

IR CAPSULES:

• Rare (0.01% to 0.1%): Reversible interstitial nephritis
• Frequency not reported: Renal dysfunction, slight BUN elevations, slight serum creatinine elevations, toxic nephropathy

CR/MR TABLETS:

• Frequency not reported: Renal dysfunction, reversible interstitial nephritis, toxic nephropathy, transient serum creatinine increase, transient serum urea/BUN increase

ORAL SUSPENSION:

• Rare (0.01% to 0.1%): Reversible interstitial nephritis
• Frequency not reported: Renal dysfunction, slight elevation in serum creatinine, slight elevation in serum urea/BUN, toxic nephropathy^[Ref]

Ocular

ER TABLETS:

• Uncommon (0.1% to 1%): Conjunctivitis^[Ref]

Immunologic

ER TABLETS:

• Uncommon (0.1% to 1%): Flu syndrome, infection

IR CAPSULES:

• Frequency not reported: Moniliasis, superinfection

CR/MR TABLETS:

• Frequency not reported: Moniliasis

ORAL SUSPENSION:

• Frequency not reported: Moniliasis, superinfection^[Ref]

See also:

Further information

Cefaclor side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

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