Those who have been following this blog for some time may have gathered that one of my pet peeves is antibiotic abuse. I am very conservative when it comes to prescribing antibiotics. However, when I think an infection is likely, I get antibiotics on board as quickly as possible. Sometimes, a few hours delay in starting antibiotics is the difference between life and death in very ill (septic) patients.
When someone is ill with an infection, they often feel quite malaised – no energy, body aches, poor appetite, fever, etc. This is because the cells of the body’s immune system produces chemicals (cytokines) to kill the invading bacteria. The process of fighting the infection utilizes a relatively large amount of energy, and the more severe the infection, the more energy is utilized, and the sicker a person feels.
When antibiotics are started for an infection, killing of the bacteria begins within minutes to hours depending on the type of antibiotic, how it is given (via an intravenous drip versus by mouth), and depending on the part of the body harboring the infection. Because of this early effect on the bacteria, many patients will begin feeling better within a few days of starting antibiotic therapy. Some patients quickly get back to their normal selves in less than no time and are fooled into thinking the infection is all gone. Not so fast!
Antibiotics should always be taken for the recommended duration of time
The complete course of antibiotic should always be taken. Different infections will require different durations of antibiotic therapy. A simple bladder infection or skin infection, or even an uncomplicated pneumonia, to name a few examples, can probably be eradicated with a course of antibiotics less than a week long.
Antibiotics for abscesses…
Deep abscesses such as those of the liver or lung or even brain, will often require several weeks of antibiotic therapy. This is because the antibiotic will probably not penetrate through to the center of the abscess but just the periphery. If it is possible to drain an abscess, then the duration of antibiotic therapy can sometimes be shortened. Between the antibiotics and the body’s immune system, the abscess gradually shrinks in size, eventually disappearing. If antibiotics are stopped before the abscess has completely resolved, bacteria in it’s center can start multiplying again, and the abscess can flare up, over a period of weeks to months. Eventually, the patient will have a relapse of the original infection.
I remember I had an elderly man with a liver abscess who I treated with antibiotics for 6 weeks. He even had a tube placed into the abscess to drain as much of the pus as possible. When the tube stopped draining it was removed. At the end of treatment I repeated his CT scan and the abscess had not completely resolved but it was significantly smaller. I felt that after 6 long weeks of antibiotics, surely the contents of the abscess cavity ought to be sterile by now.
Well…a few months later, the patient presented with fever and pain in his right side. Unfortunately, the infection relapsed and had spread from the liver abscess into his blood stream. He was retreated with antibiotics, but this time for 3 entire months! He started feeling better within days of resuming antibiotics, however he understood he had to remain on antibiotics for a long time to ensure the infection was eradicated once and for all.
Antibiotics for bone infections…
infections of the bone will require weeks and weeks of antibiotics. This is because bone is very dense and so we have to ‘hit it long and hard’ with antibiotics to ensure that all the infected bone is penetrated by the antibiotics. The idea is that all the bacteria in the substance of the bone will eventually be killed.
Eradication of bone infection is not always easy, especially when there is poor circulation. I had a patient once who I treated with antibiotics for 6 weeks for a bone infection involving one of his toes. From all appearances, the infection was gone at the end of the treatment course. Unfortunately, he presented to hospital a few months later with infection in his blood stream and the bacteria in the blood was identical to what we were treating in his toe before. We concluded that the toe was still harboring the bacteria, probably because he had poor circulation. If the circulation is poor, there is not enough blood supply to carry the antibiotic to the site of the infection. He ended up having the toe amputated.
Doses of antibiotics should never be missed
Antibiotic doses should never be skipped. Whenever a dose is missed, the concentration of the antibiotic in the blood stream and in the infected part of the body wanes. If there is no antibiotic at the site of the infection, bacteria that are still there, but dormant, can ‘wake up’ and start multiplying again. Taking another dose of antibiotic will suppress the antibiotic once more. However every time the bacteria are given a chance to ‘wake up’ they have a chance to alter themselves so that they are able to ‘hide’ from the antibiotic. This alteration in the bacteria, results in antibiotic resistance. That is, the antibiotic looses effectiveness in killing the culprit bacteria. The infection can then relapse, and testing will reveal evidence of bacterial resistance to the antibiotic. A different antibiotic (if available!) will have to be chosen to cure the infection.
Whenever you are prescribed an antibiotic, take it as instructed in order to prevent relapse of the infection after stopping it, and to prevent the bacteria being treated, from becoming resistant to the said antibiotic. Always try to have your doctor explain to you, what is being treated with the antibiotic you are prescribed.
If you think you will have trouble remembering to take an antibiotic 3 or 4 times a day, ask whether there is an alternative that you can take less frequently. Most of us now have smart phones – if there is no alternative to taking an antibiotic several times a day, set reminders in your smart phone. That’s what we have them for.
Lastly, if you are having intolerable side effects from an antibiotic, contact you doctor as soon as possible for a solution.