Condition guide
Bacterial Infections: symptoms & treatment
Bacterial infections occur when harmful bacteria multiply in the body and cause illness, affecting areas such as the skin, chest, urinary tract or throat. Many are treated effectively with antibiotics, which target bacteria but have no effect on viruses such as colds and flu. Using antibiotics correctly is essential to protect their effectiveness for the future.
Reviewed by the Kamagra AUS Pharmacy Team on 5 September 2026 · Next review June 2027
Sources for the medical information on this page
- Healthdirect Australia — Bacterial infections — Search "bacterial infection" for Australian guidance on symptoms, treatment and antibiotic use.
Recognising the signs
- Localised pain, redness, swelling or warmth, for example in the skin or a wound
- Fever, chills or generally feeling unwell
- Pain or burning when passing urine, or needing to go more often
- A persistent cough with discoloured phlegm or chest pain
- Symptoms that worsen rather than improve over a few days
Common causes
- Bacteria entering through cuts, grazes or wounds
- Urinary tract infections, more common in women
- Respiratory infections affecting the chest, throat or sinuses
- Dental and gum infections
- Contaminated food or water causing gut infections
- A weakened immune system increasing susceptibility
- Close contact with someone carrying certain bacteria
Treatment options we deliver Australia-wide
Bacterial infections are typically treated with antibiotics, and the right choice depends on the type of infection and the bacteria involved. It is important to take the full course exactly as prescribed, even if you feel better, to clear the infection fully and help prevent antibiotic resistance. Antibiotics do not work against viral illnesses, and overuse contributes to resistance, so they should only be used when genuinely needed. Always read the patient information leaflet and tell your doctor about any allergies before starting.
Lifestyle & self-care support
- Take the complete course of antibiotics exactly as directed, even once you feel well
- Never share antibiotics or use ones left over from a previous illness
- Keep cuts and wounds clean and covered while they heal
- Wash hands regularly to reduce the spread of infection
- Stay hydrated and rest to support your recovery
- Tell your doctor or pharmacist about any drug allergies before starting treatment
How to choose & when to see a doctor
Because the right antibiotic depends on the type of infection, treatment should always be guided by a doctor or qualified prescriber rather than self-selected. Seek medical advice if you suspect a bacterial infection, particularly if you have a high fever, spreading redness, or symptoms that are worsening. Read the patient information leaflet, complete the full course, and report any severe or unexpected reactions promptly.
Frequently asked questions
How do I know if my infection is bacterial or viral?
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It can be difficult to tell from symptoms alone, as both can cause fever and feeling unwell, which is why assessment by a clinician is important. Antibiotics only work against bacteria and have no effect on viruses such as colds and flu. A doctor may use your symptoms, examination and sometimes tests to decide.
Why do I need to finish the whole course of antibiotics?
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Completing the course as prescribed helps fully clear the infection and reduces the chance of surviving bacteria developing resistance. Stopping early because you feel better can allow the infection to return. Always follow the instructions in the patient information leaflet and from your prescriber.
What is antibiotic resistance?
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Antibiotic resistance is when bacteria adapt so that antibiotics no longer kill them effectively, making infections harder to treat. Overusing or misusing antibiotics speeds this up. Using them only when truly needed, and exactly as directed, helps keep them working for everyone.
Can I use leftover antibiotics from before?
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No. Leftover antibiotics may be the wrong type or dose for your current infection and using them can be ineffective or harmful, as well as contributing to resistance. Antibiotics should only be taken when prescribed for a specific infection. Always speak to a doctor or pharmacist first.
What should I do if I have a penicillin allergy?
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Always tell your doctor or pharmacist about any antibiotic or drug allergy before starting treatment, as alternative antibiotics are available. Read the patient information leaflet to check the ingredients. Seek urgent medical help if you develop a rash, swelling or breathing difficulty after taking a medicine.
Bacterial Infections health guides
UTI Symptoms in Women: What to Look Out For, and When to See a Doctor
A urinary tract infection is one of the most common bacterial infections women experience, with a fairly recognisable set of symptoms. Here's what to look for, and when it needs urgent attention.
Read guideViral or Bacterial? Why It Matters for Whether Antibiotics Will Help
Viral and bacterial infections can look identical from symptoms alone — but they respond completely differently to treatment. Here's why that distinction matters.
Read guideAntibiotic Resistance Explained
A plain-English explanation of antibiotic resistance, why finishing your full course matters, and why sharing antibiotics is never a good idea.
Read guideUTIs and Antibiotics: What to Expect
A general overview of urinary tract infections in Australia, when a doctor might prescribe an antibiotic like Bactrim DS, and what to expect.
Read guideBactrim DS Explained
What Bactrim DS treats and how its two active ingredients, sulfamethoxazole and trimethoprim, work together against bacterial infections.
Read guideAmoxicillin Dosage Strengths Explained
An overview of why amoxicillin comes in 250mg, 500mg, 650mg and 1000mg strengths, and how your doctor decides which one suits your infection.
Read guideAmoxicillin: What It Treats and How It Works
A plain-English guide to amoxicillin, the penicillin-class antibiotic used across Australia for ear, chest, urinary and skin infections, and how it works.
Read guideImportant: This information is general and not a substitute for medical advice. Always read the patient information leaflet supplied with your medicine and consult a doctor or pharmacist before starting treatment.