Late stage Lyme disease treatment might include azlocillin in the future.

Woman sleeping in car who needs late stage lyme disease treatment

A study by Stanford Medicine indicates that a drug called azlocillin “completely kills off the disease-causing bacteria Borrelia burgdorferi at the onset of the illness.” [1] In addition, the authors say, azlocillin “could be effective for treating [Lyme disease] patients infected with drug-tolerant bacteria that may cause lingering symptoms.”


Researchers identified azlocillin after screening nearly 8,000 drug compounds. They found that in the test tube and in mice, azlocillin was effective against drug-tolerant Borrelia burgdorferi s.s., the pathogen causing Lyme disease. But will late stage Lyme disease treatment soon include azlocillin, an FDA-approved drug that is often used to treat infections such as Pseudomonas aeruginosa and Escherichia coli? Stanford researchers say that is what they are working towards.

“This compound is just amazing,” says Rajadas, senior author of the study. “It clears the infection without a lot of side effects. We are hoping to repurpose it as an oral treatment for Lyme disease.”

Chronic Lyme disease

Unfortunately, treatment fails for too many patients with late stage Lyme disease. Multiple studies have shown that as many as 34% to 62% of patients have Lyme disease symptoms that persist long term despite treatment.

In fact, one study found that at their six-month follow-up visit, “36% of patients reported new-onset fatigue, 20% widespread pain, and 45% neurocognitive difficulties.”

When late stage Lyme disease treatment fails, chronic symptoms may be due, in part, to what scientists call ‘persisters,’ bacterial cells that are resistant to antibiotics.

“This compound is just amazing,” says Rajadas, senior author of the study. “It clears the infection without a lot of side effects. We are hoping to repurpose it as an oral treatment for Lyme disease.”

“These studies reveal that a small subpopulation of dormant B. burgdorferi persisters still survives with current Lyme therapy antibiotics,” says Pothineni and colleagues in the article, “Azlocillin can be the potential drug candidate against drug-tolerant Borrelia burgdorferi sensu stricto.” [1]

“The probable mechanisms as evidenced by scientific literature are the persister formation, evading the immune system by hiding in the privileged sites, surface lipoproteins modifications to avoid antigenic responses, biofilm formation, and immunomodulation,” explains Pothineni.

Azlocillin in mice

The authors inoculated mice with high doses of Borrelia burgdorferi (Bb) to test the effectiveness of each of the antibiotics. Doxycycline cleared the infection on Day 7 but did not clear the Borrelia bacteria at Days 14 and 21. Cefotaxime alone failed to eradicate the B. burgdorferi infection completely in mice who had been infected for 7 and 14 days.

Meanwhile, azlocillin completely cleared the infection in all mice but some B. burgdorferi DNA remained.

“Though the azlocillin eliminated B. burgdorferi infection completely in all the mice infected for 21 days, still 2 of 8 mice infected for 14 days had some B. burgdorferi DNA in ear tissues,” says Pothineni.

Study finds azlocillin may be a game-changer for the treatment of persistent Lyme disease symptoms. Click To Tweet

The authors points out, “the drug combinations of 40 μg/ml azlocillin and 80 μg/ml cefotaxime is much more effective in killing persisters than using azlocillin alone.”

Treatment for patients

Unfortunately, treatments that are successful in the test tube and in mice, may not work in humans.

Azlocillin is a semisynthetic β-lactam drug that cannot be used in patients who are allergic to penicillin. Currently, it is only available intravenously and the dosage, duration, efficacy, and side effects in B. burgdorferi-infected patients has not been studied.

For now, there are a number of antibiotics that are better understood including oral doxycycline, amoxicillin, cefuroxime, cefdinir, azithromycin, and clarithromycin, as well as intravenous ceftriaxone and cefotaxime. And specific drugs are available to target tick-borne co-infections, such as atovaquone and azithromycin for the treatment of Babesia.

Lastly, medications, which have recently been studied in the laboratory or in mice are now being considered as late-stage Lyme disease treatment options. These include dapsone [2], a combination of daptomycin, ceftriaxone, and doxycycline [3-5], and disulfiram. [6]

  1. Pothineni VR, Potula HSK, Ambati A, et al. Azlocillin can be the potential drug candidate against drug-tolerant Borrelia burgdorferi sensu stricto JLB31. Sci Rep. 2020;10(1):3798.
  2. Horowitz RI, Freeman PR. Precision medicine: retrospective chart review and data analysis of 200 patients on dapsone combination therapy for chronic Lyme disease/post-treatment Lyme disease syndrome: part 1. Int J Gen Med. 2019;12:101-119.
  3. Feng J, Li T, Yee R, et al. Stationary phase persister/biofilm microcolony of Borrelia burgdorferi causes more severe disease in a mouse model of Lyme arthritis: implications for understanding persistence, Post-treatment Lyme Disease Syndrome (PTLDS), and treatment failure. Discov Med. 2019;27(148):125-138.
  4. Wozel G, Blasum C. Dapsone in dermatology and beyond. Arch Dermatol Res. 2014;306(2):103-124.
  5. Gonzalez-Ruiz A, Seaton RA, Hamed K. Daptomycin: an evidence-based review of its role in the treatment of Gram-positive infections. Infect Drug Resist. 2016;9:47-58.
  6. Liegner KB. Disulfiram (Tetraethylthiuram Disulfide) in the Treatment of Lyme Disease and Babesiosis: Report of Experience in Three Cases. Antibiotics (Basel). 2019;8(2).

23 Replies to "Late stage Lyme disease treatment might include azlocillin in the future."

  • Andy
    04/28/2022 (11:20 am)

    My case began in 1988. Had an accident at work. Back and neck injuries. But I was young and strong. I had just moved Upstate NY, had 1st child. Never saw the tick or had a rash. Went downhill for a year and a half till I was diagnosed. I went through Rocephin treatments, massive antibiotics, etc. for about eight years until I recovered enough to go back to work. Staying dormant in me for a number of years. I worked hard as a bus mechanic for years. I went for pain management. I received an epidural steroid. It triggered the bacteria in my body to Full Blown Lyme symptoms the next day! Had to retire from work.
    Almost died at home. Finally was treated at a Lyme literate doctor with bicillin injections. 6 months later, back to work. I’ve had NUMEROUS other treatments since (including Dapsone which did nothing for me) and I am currently suffering again. Woe is me.
    After 35 years of living in pain and all the drama associated with it, I would gladly volunteer for a study. Please keep me updated and consider me a great test subject. Thank you and bless you helping others.

  • Linda Allen
    04/07/2022 (9:53 pm)

    My daughter has been suffering with lyme disease for years. She is a nurse but hasn’t been able to work for 4 years. She has been on an antibiotic protocol. Please let me know if this drug becomes available. Thank you!

  • Tara
    03/16/2022 (10:29 pm)

    I was diagnosed with lyme disease nearly 35 years after the onset of illness and symptoms. It is a tragic scenario that plays out everywhere. I finally got the brain scans, blood tests and treatment I needed (out of pocket of course), but the antibiotics failed miserably. I retested a few years later and I still have it. I have learned to live in a state of suffering and rejoice in the Lord! I have zero hope in any of the current treatments. It is the same with cancer. They will not release the cure. “They” want you sick and spending money. It is just the way it is. Put your hope in the Lord and look up! He is returning soon. Forget the “wisdom of man”…and seek the righteousness of God.

    • Nick C.
      04/22/2022 (10:21 pm)

      Amen Tara. I’ve only be suffering for 8+ years but as you know that’s 8+ years too much. I wish there were more awareness to our suffering. But in the meantime, our Lord knows our every suffering and is going to bring us home soon. God bless you in your health journey!

  • Leigh Davies Krohmal
    10/23/2021 (10:53 pm)

    Please let us know as soon as Azlocillin trials are available.

  • Rick Vanden Heuvel
    09/05/2021 (12:58 am)

    Dr Cameron, I certainly hope this new drug azlocillin comes out soon.
    As for so many, my life has been on hold for 14 years. Ive done just about everything I can think of or find out about. I have led Lyme support meetings and helped others as I can. But my family has 3 members with chronic lyme, and it has really messed up our lives. Tragedy has been waiting around every corner.
    Id gladly join a trial of azlocillin. Im about as detoxed as I can be. The biggest difference for me has been heavy metal chelation. In fact, I found that even small amounts of DMSA can disrupt the biofilm formation in a bigger way than antibiotics has ever done.
    Now I mostly take mother wort., enzymes, DMSA, ALA and a few others supplements. I stopped taking the imported herbs that were contaminated with metals. And it has worked out ok. But any drop of sugar or carb sends me backwards.
    WE need that Azlocillin!

  • Fred J Scholl
    08/24/2021 (8:58 am)

    Are there any study’s taking place for volunteers? I have been battling Lyme’s for 8 years now and just can’t beat it.

    • Dr. Daniel Cameron
      08/24/2021 (10:45 am)

      I have not heard of any study taking volunteers. I would encourage you to take my Lyme disease and COVID-19 survey to understand the virus or vaccine. You can participate even if you have not had the illness or taken the vaccine.

      • donald w baxley
        09/08/2021 (7:56 pm)

        I’ve had chronic lymes for 32+ yrs and would be very happy to be part study and very greatful

  • Camille Ross
    03/14/2021 (5:08 pm)

    When does he plan to start human clinical trials?

  • Susan
    01/05/2021 (7:03 pm)

    Is there any update on the efficacy of Azlocillin in humans? If this drug was already FDA approved for one illness, will it have to be re-approved for Lyme? Any chance there will be clinical trials in NY?

    • Dr. Daniel Cameron
      01/06/2021 (8:12 am)

      I have not seem any humans. The authors of the first study did not include people. The authors suggested the need for a pill version.

    • Doug Hilgers
      03/19/2022 (9:16 pm)

      Dear Susan( and Others) I am with You all and would be over the moon if Azlocillin were available in the US. I have found ( as per usual) it is already being used in the UK but to treat a different organism and in combination with another antibiotic , likely both IV. – It is available in bulk ( salt ) form for research purposes only. I do however want to point out a very promising study already concluded and demonstrating superb results of a quite old med used for an entirely different purpose: ANTATBUSE( disulfiram) that I have not hesitated to take advantage of due to its general safety ( WITH SAFE GUARDS- See YOUR PHYSICIAN) As of 2019 , in LymesDisease.Org , Dr.Dan Kinderleher has been treating up to 60 patients just in His case load .
      Google or look to That site or contact Your Provider to follow .Doug H. ( Retired R.N and long standing Lymes sufferer )- Bless You All , Brothers and Sisters!

  • James S. West
    10/01/2020 (5:58 pm)

    In 1984 I was walking through a meadow in the county of Mendocino to avoid the manzanita because of all the ticks. All at once I felt an extreme itching on my left ankle so I sat down, pulled my pantleg up and my sock down and there were two tiny little ticks stuck on my ankle about 2 inches apart. I said well I’ll be darned, I’m not safe anywhere from these things. There was a red rash and for over 6 months after starting out with the flue like symptoms I was nauseated. It went from nausea to pain in the joints and vision trouble…tunnel-vision and temporary loss of vision in one eye. After surviving and getting somewhat better but not completely free of symptoms, while living in Hawaii, I went to a neurologist. He said they didn’t have Lyme disease in Hawaii. I tried to explain about airplanes and timeframes but he was convinced that Lyme disease was not there and it was rare anywhere else. At this point in my life I have had two Western Blot tests and one other kind. Both kinds showed negative. I have a feeling that I’m going to die with this disease. What is the best test for chronic Lyme and what is the best treatment?

    • Dr. Daniel Cameron
      10/01/2020 (6:55 pm)

      Some of my patients never test positive for a tick-borne illness. There are a number of treatments. I also arrange for consultations to look for other illnesses.

  • Lori Barr
    06/27/2020 (9:12 pm)

    So happy that people in and out of the medical field have finally admitted Lyme is not cured after IV antibiotics. My poor husband has suffered from chronic Lyme for 10 yrs. and has been subjected to cruel and unnecessary criticism from many doctors, often being told to go and see a psychiatrist, it was all in his head, well considering it took a year to arrive at a diagnosis, at which time it had traveled to his CNS and has caused cognitive impairment, you might say it is in his head. 30 days of IV did not eradicate the damage.

    • Kathleen Rhodes
      11/18/2021 (10:43 am)

      I’m told same thing. Doctors tell me it’s all in my head
      5 years so far for me. My symptoms are mostly neurological

      • Fred
        03/07/2022 (3:29 pm)

        Doctors tell that it is in your head, because they do not know what is the problem. Many MDs are not educated how to detect and treat Lyme and co-infections. You have to be your own doctor, otherwise it is very nasty and deadly disease.

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