What is the dose of doxycycline (doxy) for a patient who had a tick attached for 8 hours, removed it, and subsequently developed a resolved erythema migrans (red ring)?

From the Guidelines

For a patient who had a tick attached for 8 hours and developed a red ring (which has now resolved), the recommended doxycycline dose for prophylaxis against Lyme disease is a single 200 mg dose taken orally, as stated in the guidelines by the Infectious Diseases Society of America 1. This single-dose prophylactic treatment should be administered within 72 hours of tick removal to be most effective. The 200 mg dose is appropriate for adults; for children weighing less than 45 kg (99 lbs), the dose would be 4.4 mg/kg up to the maximum 200 mg, as indicated in the clinical practice guidelines by the Infectious Diseases Society of America 1. Some key points to consider in the management of Lyme disease include:

• The tick bite is considered high-risk only if it meets specific criteria, including the tick being an identified Ixodes spp. vector species, the bite occurring in a highly endemic area, and the tick being attached for ≥36 hours 1.
• Prophylactic antibiotic therapy is recommended for adults and children within 72 hours of removal of an identified high-risk tick bite 1.
• If the patient develops symptoms of Lyme disease despite prophylaxis, a full treatment course of doxycycline would be needed (100 mg twice daily for 10-14 days for adults) 1.
• Doxycycline should be taken with a full glass of water, and the patient should remain upright for 30 minutes after taking it to prevent esophageal irritation 1.

From the FDA Drug Label

Adults: The usual dose of oral doxycycline is 200 mg on the first day of treatment (administered 100 mg every 12 hours) followed by a maintenance dose of 100 mg/day

• The dose of doxycycline for an adult is 200 mg on the first day, given as 100 mg every 12 hours, followed by 100 mg/day.
• For tick-borne illnesses, such as Lyme disease, the dosage is not explicitly stated in the provided text, but the standard dose for adults is typically 100 mg twice a day for 10 to 21 days, depending on the specific illness and clinical judgment 2.
• However, the provided text does not directly address the dosage for a patient who had a tick on for 8 hours and removed, with a red ring that has resolved.
• A conservative clinical decision would be to follow the standard dose for adults, which is 100 mg twice a day for the recommended duration, but this is not directly supported by the provided text.

From the Research

Doxycycline Dose for Lyme Disease Prophylaxis

• The dose of doxycycline for Lyme disease prophylaxis is 200 mg orally as a single dose 3
• This dose is recommended for selected patients who have had a high-risk tick bite, such as those who have had a tick attached for at least 36 hours 3
• In the case of a patient who had a tick on for 8 hours and removed, and had a red ring that has resolved, the single-dose doxycycline prophylaxis may still be considered 3
• However, it is essential to note that the efficacy and safety of doxycycline for treating Lyme disease are still controversial, and some studies have not observed significant efficacy and safety of doxycycline for treating Lyme disease 4

Considerations for Doxycycline Use

• Doxycycline is one of the antibiotics that can be used for the treatment of Lyme disease, but its relative efficacy compared to other antibiotics is not clear 5
• The quality of evidence for the use of doxycycline in Lyme disease prophylaxis is mostly low- to very low-quality, and more research is needed to determine its efficacy and safety 5
• It is crucial to consult with a healthcare professional to determine the best course of treatment for each individual case, taking into account the specific circumstances and medical history of the patient 3, 5