Antibiotic medicines are used to treat infections caused by bacteria, such as strep throat and urinary tract infection (UTI). Antibiotic medicines will not work for viral illnesses, such as colds or the flu (influenza). They work by killing the bacteria that is making you sick. Antibiotics can also have serious side effects. It is important that you take antibiotic medicines safely and only when needed.
When do I need to take antibiotics?
Antibiotics are medicines that treat bacterial infections. You may need antibiotics for:
- Urinary tract infections.
- Strep throat.
- Meningitis. This infection affects the spinal cord and brain.
- Bacterial sinusitis.
- Serious lung infection.
You may start antibiotics while your healthcare provider waits for test results to come back. Common tests may include throat, urine, blood, or mucus culture. Your healthcare provider may change or stop the antibiotic depending on your test results.
When are antibiotics not needed?
You do not need antibiotics for most common illnesses. These illnesses may be caused by a virus, not a bacteria. You do not need antibiotics for:
- The common cold.
- Sore throat.
- Discoloured mucus.
Antibiotics are not always needed for all bacterial infections. Many of these infections clear up without antibiotic treatment. Do not ask for or take antibiotics when they are not necessary.
How long should I take the antibiotic?
You must take the entire prescription. Continue to take your antibiotic for as long as advised by your healthcare provider. Do not stop taking it even if you start to feel better. If you stop taking it too soon:
- You may start to feel sick again.
- Your infection may become harder to treat.
- Complications may develop.
Each course of antibiotics needs a different amount of time to work. Some antibiotic courses last only a few days. Some last about a week to ten days. In some cases, you may need to take antibiotics for a few weeks to completely treat the infection.
What if I miss a dose?
Try not to miss any doses of medicine. If you miss a dose, call your healthcare provider or pharmacist for advice. Sometimes it is okay to take the missed dose as soon as possible.
What are the risks of taking antibiotics?
Most antibiotics can cause an infection called Clostridioides difficile (C. difficile or C. diff), which causes severe diarrhea. This infection happens when the antibiotics kill the healthy bacteria in your intestines. This allows C. diff to grow. The infection needs to be treated right away. Let your healthcare provider know if:
- You have diarrhoea while taking an antibiotic.
- You have diarrhoea after you stop taking an antibiotic. C. diff infection can start weeks after stopping the antibiotic.
Taking an antibiotic also puts you at risk for getting a bacteria that does not respond to medicine (antibiotic-resistant infection) in the future. Antibiotics can cause bacteria to change so that if the antibiotic is taken again, the medicine is not able to kill the bacteria. These infections can be more serious and, in some cases, life-threatening.
Do antibiotics affect birth control?
Birth control pills may not work while you are on antibiotics. If you are taking birth control pills, continue taking them as usual and use a second form of birth control, such as a condom, to avoid unwanted pregnancy. Continue using the second form of birth control until your healthcare provider says you can stop.
What else should I know about taking antibiotics?
It is important for you to take antibiotics exactly as told. Make sure that you:
- Take the entire course of antibiotic that was prescribed. Do not stop taking your antibiotics even if your symptoms improve.
- Take the correct amount of medicine each day.
- Ask your healthcare provider:
- How long to wait in between doses.
- If the antibiotic should be taken with food.
- If there are any foods, drinks, or medicines that you should avoid while taking the antibiotics.
- If there are any side effects you should be aware of.
- Only use the antibiotics prescribed for you by your healthcare provider. Do not use antibiotics prescribed for someone else.
- Drink a large glass of water along with the antibiotics.
- Ask the pharmacist for a syringe, cup, or spoon that properly measures the antibiotics.
- Throw away any leftover medicine.
Contact a healthcare provider if:
- Your symptoms get worse.
- You have new joint pain or muscle aches that begin after starting the antibiotic.
When should I seek immediate medical care?
- You have signs of a serious allergic reaction to antibiotics. If you have signs of a severe allergic reaction, stop taking the antibiotic right away. Signs may include:
- Hives, which are raised, itchy, red bumps on the skin.
- Skin rash.
- Trouble breathing.
- A wheezing sound when you breathe.
- Swelling anywhere on your body.
- Feeling dizzy.
- Your urine turns dark or becomes blood-coloured.
- Your skin turns yellow.
- You bruise or bleed easily.
- You have severe diarrhoea and abdominal cramps.
- You have a severe headache.
- Antibiotic medicines are used to treat infections caused by bacteria, such as strep throat and UTIs. It is important that you take antibiotic medicines only when needed.
- Your healthcare provider may change or stop the antibiotic depending on your test results.
- Most antibiotics can cause an infection called Clostridioides difficile (C. difficile or C. diff), which causes severe diarrhoea. Let your health care provider know if you develop diarrhoea while taking an antibiotic.
- Take the entire course of antibiotic that was prescribed.
This information is not intended to replace advice given to you by your healthcare provider. Make sure you discuss any questions you have with your healthcare provider.
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Updated on 22 April 2021 by CaregiverAsia.
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