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Spectrobid Side Effects

Generic name: bacampicillin

Medically reviewed by Last updated on Apr 15, 2023.

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

Applies to bacampicillin: oral tablet.


Take all of the bacampicillin that has been prescribed for you even if you begin to feel better. Your symptoms may begin to improve before the infection is completely treated.

Bacampicillin may decrease the effectiveness of birth control pills. Use a second method of birth control while taking bacampicillin to ensure protection from unintended pregnancy.

If you experience any of the following serious side effects, stop taking bacampicillin (the active ingredient contained in Spectrobid) and seek emergency medical attention or contact your doctor immediatley:

Other, less serious side effects may be more likely to occur. Continue to take bacampicillin and talk to your doctor if you experience

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

For Healthcare Professionals

Applies to bacampicillin: oral tablet.


Hypersensitivity reactions occur in up to 5% of patients treated with bacampicillin (the active ingredient contained in Spectrobid) Such reactions may include urticarial rashes, edema, hypotension, fever, eosinophilia, Stevens-Johnson syndrome, and dyspnea. Anaphylaxis is rare. Bacampicillin should not be given to patients with a penicillin allergy.[Ref]

Besides the urticarial rash of hypersensitivity to bacampicillin, a delayed hypersensitivity maculopapular rash may occur 10 to 12 days after bacampicillin therapy is begun.

Hypersensitivity reactions have included rare cases of interstitial nephritis, Henoch-Schonlein Purpura, focal glomerulonephritis and Stevens-Johnson syndrome.[Ref]


Gastrointestinal adverse effects occur in 2% to 5% of treated patients and may include diarrhea, nausea, vomiting, and abdominal cramps. Rare cases of hepatitis and pancreatitis have been reported with ampicillin, the active form of bacampicillin (the active ingredient contained in Spectrobid) Monitoring of liver function tests is recommended in patients with liver dysfunction.[Ref]

Bacampicillin-associated diarrhea is usually self-limited and is likely related to alterations in the intestinal microflora. Such alterations may predispose patients to the development of diarrhea from Clostridium difficile toxin. Rare cases of transiently increased liver function tests and chronic cholestasis associated with ampicillin have been reported.

Acute pancreatitis associated with ampicillin has been reported and confirmed by rechallenge with ampicillin in a patient with no other obvious cause of pancreatitis.[Ref]


Hematologic adverse effects of bacampicillin (the active ingredient contained in Spectrobid) are rare and include thrombocytopenia, red cell aplasia, and anemia.[Ref]

Rare cases of thrombocytopenia, leukopenia, red cell aplasia, and anemia have been reported.[Ref]


1. Craig WA, Gerber AU (1981) "Worldwide experience with bacampicillin administered twice a day." Rev Infect Dis, 3, p. 171-7

2. Cavanzo FJ, Garcia CF, Botero RC (1990) "Chronic cholestasis, paucity of bile ducts, red cell aplasia, and the Stevens-Johnson syndrome." Gastroenterology, 99, p. 854-6

3. Grafford K, Nilsson BS (1981) "Twice daily dosage of bacampicillin: a summary of clinical documentation." J Antimicrob Chemother, 8, p. 119-27

4. Blomqvist M, Hedtrom SA (1987) "The clinical efficacy and safety of bacampicillin twice daily in comparative studies." J Int Med Res, 15, p. 32-43

5. Hjort N, Renmarker K, Rosberg B, Skog PA, Hey H (1983) "Tolerance of two ampicillin esters: a comparison of pivampicillin and bacampicillin." Pharmatherapeutica, 3, p. 398-404

6. Roujeau JC, Kelly JP, Naldi L, et al. (1995) "Medication use and the risk of Stevens-Johnson syndrome or toxic epidermal necrolysis." N Engl J Med, 333, p. 1600-7

7. Berliner S, Sidi Y, Shaklai M, Pinkhas J (1982) "Appearance of thrombocytopenia and benign monoclonal gammopathy following intake of drugs." Acta Haematol, 67, p. 71-2

8. Hughes GS (1983) "Ampicillin and hematologic effects." Ann Intern Med, 99, p. 573

9. (2002) "Product Information. Spectrobid (bacampicillin)." Roerig Division

Further information

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

Some side effects may not be reported. You may report them to the FDA.