Common Infections: Which Need Antibiotics and Which Don’t

Some common infections, such as most urinary tract infections (UTIs), usually need antibiotics. Others, including most chest infections, sinus infections, earaches and sore throats, are often caused by viruses or get better on their own. Knowing which is which helps you get the right treatment and avoid antibiotics that won’t help.

Here’s a condition-by-condition guide to the infections people most often see a GP about, when antibiotics may be considered, what helps in the meantime and when to get help.

At a glance

This table is a general guide only. A doctor will consider your symptoms, how long you’ve been unwell and your overall health.

Urinary tract infections (UTIs)

UTIs are caused by bacteria, usually from the bowel, getting into the urinary tract. Symptoms include stinging or burning when you wee, needing to go often or urgently, and cloudy or strong-smelling urine. Most UTIs are bladder infections.

Some mild UTIs settle by themselves, but many need antibiotics, so it’s worth speaking to a doctor. A urine test may be needed to confirm the infection and check which antibiotic will work, particularly if you’re pregnant, male, or keep getting UTIs.

See a doctor promptly if you have fever, chills, back or side pain or vomiting, as these can be signs the infection has spread to the kidneys. Our guide to UTIs in women covers symptoms, prevention and recurrent UTIs in more detail, and Thrush, BV or UTI? explains how to tell similar conditions apart.

Chest infections

“Chest infection” usually means either acute bronchitis (infection of the airways) or pneumonia (infection of the lungs).

Acute bronchitis

Most chest infections in healthy adults are viral and get better on their own. The cough can last 2 to 3 weeks, and sometimes longer, as the airways recover. Antibiotics don’t help viral bronchitis.

Pneumonia

Pneumonia is more serious. It can cause fever, a cough with phlegm, shortness of breath, fast breathing and chest pain when you breathe in. Bacterial pneumonia usually needs antibiotics, and some people need hospital care. Pneumonia often needs a physical examination and sometimes a chest X-ray, so a telehealth doctor may ask you to be seen in person.

See a doctor if you’re short of breath, have a high fever, cough up blood, or your symptoms are getting worse or not improving.

Earaches and middle ear infections

Middle ear infections (otitis media) are very common in children and often follow a cold. They cause ear pain, and sometimes fever, irritability or temporary hearing loss. According to healthdirect, most middle ear infections go away on their own within about a week, and antibiotics only slightly reduce pain while adding the risk of side effects.

Doctors are more likely to recommend antibiotics for children under 2, Aboriginal and Torres Strait Islander children, children with certain medical conditions, or anyone who seems very unwell. Pain relief is an important part of treatment, and your pharmacist can advise on suitable options and doses for children.

Earache can also come from an outer ear infection (swimmer’s ear), wax, or problems in the jaw or teeth. A doctor usually needs to look inside the ear with an instrument to diagnose an ear infection, which can’t be done by video, so you may be asked to see a GP in person.

Sinusitis

Sinusitis is inflammation of the sinuses, the air-filled spaces around your nose and eyes. It usually follows a cold and is usually viral. Symptoms include a blocked or runny nose, facial pain or pressure, and reduced sense of smell.

Most sinusitis gets better without antibiotics. Saline sprays or rinses, steam and simple pain relief may help. A doctor may consider antibiotics if symptoms are severe, last more than about 10 days without improving, or get better then worse again.

Get urgent help if you have swelling or redness around the eye, changes in your vision, a severe headache, a stiff neck or confusion. These can be signs of a rare but serious complication.

Sore throats

Most sore throats are caused by viruses and settle within about a week. Bacterial throat infections, such as strep throat, are less common and may need antibiotics, particularly in people at higher risk of complications. Our article on tonsillitis explains more.

Other infections that often need antibiotics

• Skin infections such as cellulitis or an infected wound. Spreading redness, warmth and swelling need prompt assessment, and a doctor often needs to see the area.
• Some sexually transmitted infections, such as chlamydia and gonorrhoea. Testing is important before treatment. See STI testing and treatment.

For a broader look at deciding whether you need antibiotics, read Do you need antibiotics? When they help and when they don’t. To understand why careful use matters, see Antibiotics and antibiotic resistance.

When to get urgent help

Call 000 or go to your nearest emergency department if you or someone you care for has:

• difficulty breathing, or chest pain
• confusion, drowsiness, or is hard to wake
• a high fever with shaking chills, or severe back or side pain
• a stiff neck, severe headache or a rash that doesn’t fade when pressed
• redness and swelling that is spreading quickly
• swelling or redness behind the ear, or the ear being pushed forward
• trouble swallowing, drooling, or can’t keep fluids down

How Teldoc can help

Our AHPRA-registered GPs can assess many common infections by phone or video, 7 days a week from 9 am to 7 pm (Sydney time). Most patients are seen within 15 minutes. Your doctor can:

• talk through your symptoms and check for warning signs
• prescribe treatment if clinically appropriate, with an eScript sent to your phone
• arrange urine tests, swabs or other tests through our pathology and radiology referrals
• provide a medical certificate if you need time off
• tell you if you need to be examined in person, for example to look in your ears or listen to your chest

General consultations are $55 on weekdays and $75 on weekends and public holidays. STI consultations are bulk billed for eligible patients with a valid Medicare card. See our fees page, or read more about online UTI treatment and antibiotic prescriptions.

Frequently asked questions

Do all UTIs need antibiotics?

Not all, but many do. Some mild bladder infections settle on their own, but a doctor should assess UTI symptoms, especially if you’re pregnant, male, have a fever or back pain, or keep getting infections.

Do ear infections need antibiotics?

Often not. Most middle ear infections get better on their own within about a week. Antibiotics may be recommended for young children under 2, Aboriginal and Torres Strait Islander children, and anyone who is very unwell.

Is a chest infection bacterial or viral?

Most chest infections in healthy adults, such as acute bronchitis, are viral and don’t need antibiotics. Pneumonia can be bacterial and may need antibiotics, so see a doctor if you’re short of breath or have a high fever.

When does sinusitis need antibiotics?

Most sinusitis is viral and settles without antibiotics. A doctor may consider them if symptoms are severe, last more than about 10 days without improving, or get better and then worse again.

Can a telehealth GP diagnose an ear infection?

A telehealth GP can talk through your symptoms and advise on pain relief, but diagnosing an ear infection usually requires looking inside the ear. Your doctor will tell you if you need to be seen in person.

This article is general health information and isn’t a substitute for advice from your own doctor. If you’re worried about your health, speak to a GP. In an emergency, call 000.

Medically reviewed by Dr Vafa Derakshan (MBBS, FRACGP), September 2026