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Drug Interactions between ampicillin and typhoid vaccine, live

This report displays the potential drug interactions for the following 2 drugs:

  • ampicillin
  • typhoid vaccine, live

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Interactions between your drugs


ampicillin typhoid vaccine, live

Applies to: ampicillin and typhoid vaccine, live

ADJUST DOSING INTERVAL: The use of live, attenuated oral typhoid vaccine with antibacterial sulfonamides or other antibiotics may result in a diminished immunologic response to the vaccine. Some antibiotics may be active against the vaccine strain of Salmonella typhi (Ty21a), thereby preventing a sufficient degree of multiplication to occur in order to induce a protective immune response. Several antimalarial drugs such as chloroquine, mefloquine, and pyrimethamine-sulfadoxine also possess antibacterial activity, but concomitant administration did not significantly reduce immune response to the vaccine or compromise its efficacy in healthy adult study subjects. By contrast, concomitant administration of proguanil did cause a significant decrease in the immune response rate. The effects of other antimalarial agents have not been studied.

MANAGEMENT: Live, attenuated oral typhoid vaccine should not be administered during and for at least 3 days before and after treatment with antibacterial sulfonamides or other antibiotics. A longer interval should be considered following treatment with long-acting antibiotics (e.g., azithromycin). If malaria prophylaxis is needed, the same 3-day interval at the minimum should be observed between antimalarials and the vaccine. However, chloroquine, mefloquine, and pyrimethamine-sulfadoxine may be given concomitantly with the vaccine. Alternatively, parenteral typhoid vaccine (typhoid Vi polysaccharide vaccine) may be considered if coadministration with antibacterial agents is required.


  1. American Medical Association, Division of Drugs and Toxicology "Drug evaluations annual 1994." Chicago, IL: American Medical Association; (1994):
  2. CDC. Centers for Disease Control and Prevention "Typhoid & Paratyphoid Fever. Available from: URL:" ([2013]):
  3. UK government "Typhoid. Available from: URL:" ([cited 2014]):
  4. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
View all 4 references

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Drug and food interactions


ampicillin food

Applies to: ampicillin

ADJUST DOSING INTERVAL: Certain penicillins may exhibit reduced gastrointestinal absorption in the presence of food. The therapeutic effect of the antimicrobial may be reduced.

MANAGEMENT: The interacting penicillin should be administered one hour before or two hours after meals. Penicillin V and amoxicillin are not affected by food and may be given without regard to meals.


  1. McCarthy CG, Finland M "Absorption and excretion of four penicillins." N Engl J Med 263 (1960): 315-26
  2. Neu HC "Antimicrobial activity and human pharmacology of amoxicillin." J Infect Dis 129 (1974): s123-31
  3. Klein JO, Sabath LD, Finland M "Laboratory studies on oxacillin. I: in vitro activity against staphylococci and some other bacterial pathogens. II: absorption and urinary excretion in normal young." Am J Med Sci 245 (1963): 399-411
  4. Cronk GA, Wheatley WB, Fellers GF, Albright H "The relationship of food intake to the absorption of potassium alpha-phenoxyethyl penicillin and potassium phenoxymethyl penicillin from the gastrointestinal tract." Am J Med Sci 240 (1960): 219-25
  5. Neuvonen PJ, Elonen E, Pentikainen PJ "Comparative effect of food on absorption of ampicillin and pivampicillin." J Int Med Res 5 (1977): 71-6
  6. Welling PG, Huang H, Koch PA, Madsen PO "Bioavailability of ampicillin and amoxicillin in fasted and nonfasted subjects." J Pharm Sci 66 (1977): 549-52
View all 6 references

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Therapeutic duplication warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.