From the Guidelines
Antibiotics such as trimethoprim-sulfamethoxazole, penicillins, and tetracyclines can cause bone marrow suppression, particularly when used in combination with other medications like methotrexate, and their effects can be mitigated by monitoring blood counts regularly and adjusting doses as necessary. To minimize the risk of bone marrow suppression, healthcare providers should be cautious when prescribing antibiotics to patients taking methotrexate, as the combination of these medications can increase the risk of toxicity [ 1 ]. Some key points to consider when prescribing antibiotics to patients at risk of bone marrow suppression include:
- Monitoring blood counts regularly, particularly in patients with renal impairment or those taking other myelosuppressive medications
- Adjusting antibiotic doses as necessary to minimize the risk of toxicity
- Considering alternative antibiotics for high-risk patients, such as those with pre-existing hematologic disorders
- Educating patients about the symptoms of bone marrow suppression, including unusual bleeding, bruising, fatigue, and increased susceptibility to infections, and instructing them to seek immediate medical attention if these develop [ 1 ]. In severe cases of bone marrow suppression, granulocyte colony-stimulating factors like filgrastim may be administered to stimulate neutrophil production, and patients should be monitored carefully for signs of sepsis and treated accordingly [ 1 ]. The mechanism behind antibiotic-induced bone marrow suppression varies by drug class, but often involves direct toxicity to hematopoietic stem cells or immune-mediated destruction of blood cell precursors. Healthcare providers should prioritize the safety of their patients by carefully considering the potential risks and benefits of antibiotic therapy, particularly in patients at high risk of bone marrow suppression.
From the FDA Drug Label
Chronic Use of sulfamethoxazole and trimethoprim at high doses and/or for extended periods of time may cause bone marrow depression manifested as thrombocytopenia, leukopenia and/or megaloblastic anemia. Signs of acute overdosage with trimethoprim include ... bone marrow depression If signs of bone marrow depression occur, the patient should be given leucovorin 5 to 15 mg daily until normal hematopoiesis is restored.
Antibiotics that can cause bone marrow suppression:
- Trimethoprim-sulfamethoxazole 2 Effects mitigation:
- Monitor blood counts and appropriate blood chemistries, including electrolytes
- Administer leucovorin 5 to 15 mg daily if signs of bone marrow depression occur, until normal hematopoiesis is restored
- Institution of gastric lavage or emesis, forcing oral fluids, and the administration of intravenous fluids if urine output is low and renal function is normal.
From the Research
Antibiotics Causing Bone Marrow Suppression
- Chloramphenicol has been associated with suppression of the bone marrow and aplastic anemia 3
- Trimethoprim-sulfamethoxazole has been linked to neutropenia, although the incidence was lower in patients receiving folinic acid 4
- Metronidazole may cause reversible neutropenia 3
Mitigating the Effects of Bone Marrow Suppression
- Folinic acid may help reduce the incidence of neutropenia associated with trimethoprim-sulfamethoxazole 4
- Optimizing drug dosing and duration may help minimize the emergence of resistance and reduce the risk of bone marrow suppression 5
- Alternative antibiotics, such as linezolid or doxycycline, may be considered for patients at risk of bone marrow suppression 6, 7