Lyme disease can affect the inner ear: a 2024 Danish study found reduced cochlear function in two-thirds of 25 patients with Lyme neuroborreliosis, though whether Lyme explains tinnitus without other signs of infection is much less certain.
Lyme neuroborreliosis is the form of Lyme disease that reaches the nervous system, and the ear sits at the edge of that territory. The article on sudden sensorineural hearing loss covers acute hearing loss broadly; this page covers what is and is not known about the Lyme connection specifically, because the numbers circulating about it are often quoted without their context.
What the numbers show
A tick-borne disease clinic in Poland. A 2018 study enrolled 216 adults aged 18 to 55 who attended an outpatient clinic for tick-borne diseases between 2014 and 2016, diagnosed with Lyme disease and co-infections. 162 had ear, nose or throat symptoms, and among them tinnitus was the most common complaint (76.5%), ahead of vertigo and dizziness (53.7%), headache (39%) and one-sided sensorineural hearing loss (16.7%). Many patients also had other tick-borne infections, most often Bartonella. That is a specialist clinic population with no comparison group, so it shows tinnitus is common among people attending such a clinic — not how often Lyme disease causes tinnitus in general.
People in hospital with sudden hearing loss. A 2021 study from the same Polish research group tested 86 people admitted with sudden sensorineural hearing loss in 2017 and 2018. Nine (10.5%) had antibodies to Borrelia burgdorferi, and all nine had partial or complete recovery of hearing after antibiotic treatment. The authors recommend Borrelia testing as part of the workup for sudden hearing loss.
The other side of that argument. An evidence-based review in Otolaryngology–Head and Neck Surgery found two studies that answered the question directly. They reported Borrelia antibodies in 16% of people with sudden hearing loss against 13.5% of the general population — and among those patients, no one with definite neuroborreliosis. Its conclusion was that neuroborreliosis seems to be a rare cause of sudden hearing loss and that routine antibody screening should not be recommended. The 2019 US guideline on sudden hearing loss goes further in general terms, making it a strong recommendation that clinicians not order routine laboratory tests for sudden hearing loss.
Those findings fit together once you separate exposure from cause. Antibodies show that someone has met the bacterium at some point, which in an area where Lyme disease is common describes a meaningful share of the population. They do not show that the infection is what damaged the ear. Testing earns its place when the story points at Lyme — not as a routine screen. Otosyphilis, another treatable infection of the inner ear, raises the same question about who should be tested.
How Lyme disease reaches the inner ear
The 2021 Polish study's authors propose that Borrelia burgdorferi infection can cause inflammatory and vascular changes that affect the cochlea or the auditory nerve, and that the longer an infection lasts, the more likely those changes are to become permanent. That is the same broad route — inflammation and disturbed blood supply to the inner ear — seen with other infectious and inflammatory causes of sudden hearing loss.
Facial nerve palsy is a common feature of neuroborreliosis: 10 of the 25 patients in the Danish study below had it. A 2022 case report describes a woman in her 40s whose hearing loss in both ears and tinnitus, developing over three days with dizziness, were eventually traced to Lyme neuroborreliosis — after she had been sent home from two other emergency departments. One-sided facial weakness has its own causes, covered in Bell's palsy and tinnitus, and Lyme disease is one of the things worth asking about when it arrives alongside ear symptoms.
What objective testing found
The strongest direct evidence comes from a 2024 study at a Danish hospital, which measured cochlear function with otoacoustic emissions — a test of the inner ear's hair cells — in 25 patients admitted with Lyme neuroborreliosis, at admission and again at follow-up.
- Cochlear function was temporarily or permanently reduced in two-thirds of the patients.
- On standard hearing tests, sensorineural hearing loss was present in 11 of 23 at discharge and 9 of 16 sixty days after discharge.
- Only 2 patients had complained of hearing loss on admission.
- Cochlear function improved in 14 of 18 patients between admission and follow-up at low and middle frequencies, while it declined at the highest frequencies — high-frequency hearing loss that remained.
The authors describe this as likely the first firm documentation of cochlear involvement in neuroborreliosis. They also stop short of recommending routine hearing screening for everyone with the condition, saying new studies are needed before that recommendation can be made beyond people with specific complaints. The patients' median age was 56, so some of the hearing loss found on standard tests may have preceded the infection; the changes in cochlear function measured over time in the same patients are the more direct evidence.
What this means practically
- New tinnitus, hearing loss or dizziness after a tick bite, or in an area where Lyme disease is common, is worth mentioning to a doctor together with any other Lyme features — a spreading rash, facial weakness, nerve pain, fatigue. The combination is what makes testing sensible.
- Sudden hearing loss is urgent whatever its cause. Do not wait on a Lyme test to be seen; the sudden hearing loss article linked above covers what the first days involve.
- If you are being treated for Lyme neuroborreliosis and notice any hearing change, ask for a hearing test. The Danish study found hearing loss common in this group and rarely complained of.
- Tinnitus on its own, with no other features of Lyme disease, is not something this evidence explains. What the whole range of causes looks like is the better starting point, and tinnitus and hearing loss covers the commonest one.