From the Guidelines
Taking amoxicillin with doxycycline is not recommended as a first-line treatment for Lyme disease prophylaxis, as doxycycline is the preferred choice, and amoxicillin should only be considered in cases where doxycycline is contraindicated 1. When considering the use of antibiotics for prophylaxis after a tick bite, the risk of infection with B. burgdorferi must be weighed against the potential risks and benefits of antibiotic treatment.
- The typical adult dose for doxycycline is 100mg twice daily, and it should be taken either 1 hour before or 2 hours after meals for optimal absorption.
- Amoxicillin is not the preferred choice for Lyme disease prophylaxis, but if used, the typical adult dose is 250-500mg three times daily or 875mg twice daily.
- Common side effects of both antibiotics include digestive upset, and patients should contact their doctor if they experience severe diarrhea, rash, or allergic reactions.
- It is essential to note that doxycycline is relatively contraindicated in pregnant women and children < 8 years old, and amoxicillin may be considered as an alternative in these cases, but only if the benefits outweigh the risks 1.
- The decision to use antibiotic prophylaxis after a tick bite should be made on a case-by-case basis, taking into account the individual's risk factors and the local rate of infection with B. burgdorferi 1.
From the Research
Taking Amoxicillin with Doxycycline
- The combination of amoxicillin and doxycycline has been studied in various contexts, including the treatment of Lyme disease and respiratory infections 2, 3.
- A study published in 2020 found that doxycycline had a high susceptibility rate against bacterial isolates, including those resistant to amoxicillin 4.
- Another study from 2009 found that oral amoxicillin and doxycycline were first-line treatment options for early stage Lyme borreliosis 2.
- In vitro susceptibility testing of Borrelia burgdorferi sensu stricto strains found that doxycycline and amoxicillin were effective against the bacteria, although the minimum inhibitory concentrations (MICs) varied 5.
- A comparative assessment of doxycycline and amoxycillin in respiratory infections found that both antibiotics were equally effective in providing prompt improvement and complete resolution of the infection 3.
- A review of diagnosis, treatment, and prevention of Lyme disease, human granulocytic anaplasmosis, and babesiosis found that oral doxycycline, amoxicillin, and cefuroxime axetil were effective for treating Lyme disease, and that doxycycline was effective for treating erythema migrans and early neurologic Lyme disease 6.
Efficacy and Safety
- The efficacy of amoxicillin and doxycycline in combination has not been extensively studied, but individual studies suggest that both antibiotics are effective against various bacterial infections 4, 2, 5, 3, 6.
- The safety of taking amoxicillin with doxycycline has not been specifically addressed in the available studies, but both antibiotics are generally considered safe when used individually 4, 2, 5, 3, 6.
Clinical Applications
- The combination of amoxicillin and doxycycline may be considered for the treatment of Lyme disease, respiratory infections, and other bacterial infections, although the specific clinical application would depend on the individual patient's condition and medical history 2, 3, 6.
- Further studies are needed to fully understand the efficacy and safety of taking amoxicillin with doxycycline, as well as the optimal dosing regimens and treatment durations 4, 2, 5, 3, 6.