Amoxicillin / Vonoprazan Side Effects

Medically reviewed by Drugs.com. Last updated on Apr 10, 2025.

Applies to amoxicillin / vonoprazan: oral capsule, oral tablet.

Precautions

It is important that your doctor check your progress at regular visits. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to use it. Blood tests may be needed to check for unwanted effects. If your condition does not improve, or if it becomes worse, discuss this with your doctor.

Do not use this medicine together rilpivirine ((Edurant®) or products containing rilpivirine (eg, Complera®, Odefsey®). Using these medicines together may increase risk for more serious side effects.

This medicine may cause serious allergic reactions, including anaphylaxis and angioedema, which can be life-threatening and require immediate medical attention. Call your doctor right away if you have chest tightness, rash, itching, fast heartbeat, trouble breathing or swallowing, or large, hive-like swelling of the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs while you are using this medicine.

Check with your doctor right away if you have blistering, peeling, or loosening of the skin, chills, cough, diarrhea, itching, joint or muscle pain, red irritated eyes, red skin lesions, often with a purple center, sore throat, sores, ulcers, or white spots in the mouth or on the lips, or unusual tiredness or weakness. These may be symptoms of serious skin reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis.

This medicine may cause diarrhea, and in some cases it can be severe. It may occur 2 months or more after you Stop taking amoxicillin / vonoprazan. Do not take any medicine to treat diarrhea without first checking with your doctor. If you have any questions or if mild diarrhea continues or gets worse, check with your doctor.

Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Serious side effects

Along with its needed effects, amoxicillin / vonoprazan may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking amoxicillin / vonoprazan:

For healthcare professionals

Applies to amoxicillin / vonoprazan: oral kit.

General adverse events

The most common adverse reaction leading to discontinuation of this product was rash.^[Ref]

Cardiovascular

• Common (1% to 10%): Hypertension (includes increased blood pressure)
• Frequency not reported: QT prolongation, tachycardia^[Ref]

Dermatologic

• Frequency not reported: Dermatitis, dry skin, rash

Amoxicillin and Vonoprazan:

• Frequency not reported: Severe cutaneous adverse reactions (including Stevens-Johnson syndrome, toxic epidermal necrolysis)

Amoxicillin:

• Frequency not reported: Erythematous skin rash
• Postmarketing reports: Mucocutaneous candidiasis, erythematous maculopapular rashes, erythema multiforme, exfoliative dermatitis, urticaria, toxic epidermal necrolysis, Stevens-Johnson syndrome, drug reaction with eosinophilia and systemic symptoms (DRESS), acute generalized exanthematous pustulosis

Vonoprazan:

• Postmarketing reports: Urticaria, drug eruption, erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis^[Ref]

Gastrointestinal

• Common (1% to 10%): Diarrhea, abdominal pain (includes abdominal discomfort, abdominal pain, lower abdominal pain, upper abdominal pain)
• Frequency not reported: Abdominal distension, constipation, dry mouth, duodenal polyp, duodenal ulcer, dyspepsia, flatulence, gastric ulcer, gastroesophageal reflux disease, hematochezia, large intestine polyp, nausea, rectal polyp, stomatitis, tongue discomfort, vomiting, anal fungal infection, gastrointestinal viral infection, oral fungal infection, tongue fungal infection

Amoxicillin:

• Frequency not reported: Clostridioides difficile-associated diarrhea
• Postmarketing reports: Black hairy tongue, hemorrhagic/pseudomembranous colitis, tooth discoloration (brown, yellow, or gray staining)

Acid-Suppressing Therapies:

• Frequency not reported: C difficile-associated diarrhea^[Ref]

Onset of pseudomembranous colitis symptoms has been reported during or after antibacterial treatment.

Most reports of tooth discoloration with amoxicillin occurred in pediatric patients; discoloration was reduced/eliminated with brushing or dental cleaning in most cases.^[Ref]

Genitourinary

• Common (1% to 10%): Vulvovaginal candidiasis (includes urogenital fungal infection, vulvovaginal candidiasis, vulvovaginal mycotic infection, vulvovaginal pruritus, genital pruritus, genital fungal infection)
• Frequency not reported: Urinary tract infection, vaginal discharge

Amoxicillin:

• Postmarketing reports: Crystalluria^[Ref]

Hematologic

• Frequency not reported: Anemia, leukocytosis, leukopenia, neutropenia

Penicillins:

• Postmarketing reports: Hemolytic anemia, thrombocytopenia, thrombocytopenic purpura, eosinophilia, agranulocytosis^[Ref]

Hemolytic anemia, thrombocytopenia, thrombocytopenic purpura, eosinophilia, and agranulocytosis have been reported during therapy with penicillins; these reactions were usually reversible when therapy was stopped and were believed to be hypersensitivity phenomena.^[Ref]

Hepatic

• Frequency not reported: Abnormal liver function test

Vonoprazan:

• Postmarketing reports: Hepatic injury, hepatic failure, jaundice^[Ref]

Hypersensitivity

• Frequency not reported: Drug hypersensitivity

Amoxicillin and Vonoprazan:

• Frequency not reported: Hypersensitivity reactions (e.g., anaphylaxis, anaphylactic shock, rash, erythema multiforme, Henoch-Schonlein purpura)

Amoxicillin:

• Postmarketing reports: Anaphylaxis, serum sickness-like reactions, hypersensitivity vasculitis

Vonoprazan:

• Postmarketing reports: Anaphylactic shock^[Ref]

Metabolic

• Frequency not reported: Decreased appetite^[Ref]

Musculoskeletal

• Frequency not reported: Bone fracture^[Ref]

Nervous system

• Common (1% to 10%): Headache
• Uncommon (0.1% to 1%): Dysgeusia (includes taste disorder)
• Frequency not reported: Ageusia, dizziness, tension headache

Amoxicillin:

• Postmarketing reports: Reversible hyperactivity, convulsions, aseptic meningitis^[Ref]

Ocular

• Frequency not reported: Orbital edema^[Ref]

Other

• Frequency not reported: Fatigue, pyrexia, viral infection^[Ref]

Psychiatric

• Frequency not reported: Anxiety, depression, insomnia

Amoxicillin:

• Postmarketing reports: Agitation, confusion, behavioral changes^[Ref]

Renal

• Frequency not reported: Renal hypertrophy, tubulointerstitial nephritis^[Ref]

Respiratory

• Common (1% to 10%): Nasopharyngitis
• Frequency not reported: Pneumonia, upper respiratory tract infection, cough, nasal polyps, oropharyngeal pain^[Ref]

See also:

Further information

Amoxicillin/vonoprazan 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.

Medical Disclaimer