Ampicillin

Oral health effects

• Oral candidiasis (thrush)

  Broad-spectrum antibiotics suppress commensal bacteria, allowing Candida overgrowth in the mouth.

  Mechanism: Loss of competitive inhibition from normal flora.

  Clinical management: Watch for thrush, especially with repeated courses; treat with an antifungal; reinforce hygiene.

• Antibiotic-associated diarrhea / gut dysbiosis

  Disruption of gut flora can cause diarrhea and C. difficile overgrowth.

  Clinical management: A probiotic (e.g., Saccharomyces boulardii) during the course may modestly lower the risk of antibiotic-associated diarrhea; the evidence is low certainty. Avoid probiotics in immunocompromised or severely ill patients. See the Gut Health page.

• Sore mouth or tongue (glossitis, stomatitis)

  Glossitis and stomatitis are listed adverse reactions and are usually linked to oral dosage forms. Some patients report a sore mouth or tongue. Frequency not stated.

  Clinical management: Bland rinses (saline or sodium bicarbonate) and a soft toothbrush. Avoid irritating products. Check for candidiasis. Refer to the prescriber if lesions are severe or come with a rash, because ampicillin rash can involve the oral mucosa.