Do I need antibiotics for my UTI?

A UTI, or urinary tract infection, occurs when bacteria which doesn’t normally live in the urinary system enters a part of it — this might be the urethra (the tube urine travels down in from the bladder to outside the body), the bladder itself, the ureter (the tube connecting the kidneys to the bladder), or even sometimes the kidneys.

UTIs are considered to be one of the most common bacterial infections,¹ and they can be caused by different types of bacteria. Equally, however, some bacteria are present normally in the urinary system and cause no harm at all, so bacteria being present in urine therefore does not necessarily mean you have a UTI.²

The most common causative bacteria for UTIs are those from the bowel, which are able to make their way into the urinary tract due to how close the anus is to the opening of the urethra. This distance is much shorter in cisgender women than men, which is why women generally get UTIs more frequently.³

There are lots of things which can make a person more susceptible to UTI infections. These include being assigned female at birth, being over 65 years old, having an abnormality in the urinary tract, “instrumentation” of the urinary tract (for example, having a catheter or a uroscopy), being sexually active, having a new sexual partner, being pregnant, having a problem with the immune system, or having diabetes.

What are the symptoms of a UTI?

The most common symptoms of a UTI are pain, burning or stinging when passing urine, needing to pass urine more than usual, feeling the need to pass urine urgently, and/or pain in the lower abdomen. Sometimes the frequency of needing to urinate can be extreme, which may cause embarrassment. There can be many other symptoms too, such as seeing blood in the urine or feeling generally run down or poorly.

The most common symptoms of a UTI are pain, burning or stinging when passing urine, needing to pass urine more than usual, feeling the need to pass urine urgently, and/or pain in the lower abdomen

Involvement of the kidneys in a UTI is known as a complicated UTI, and this is also the term used to describe other, more serious UTIs, for example UTIs in pregnant people, in people with a weak immune system, in people who have had a kidney transplant, or in people who are catheterised or who have kidney stones.⁴ Treatment for complicated UTIs, and symptoms you will notice if a UTI has spread to your kidneys, are discussed in more detail below.

Do UTIs need treatment with antibiotics?

Currently, guidelines advise that even people with “uncomplicated” UTIs are offered antibiotics, depending on the severity of symptoms.⁵ If you only have mild symptoms, you can try waiting for up to 48 hours to see if the infection settles down by itself, for example, if it is not convenient for you to see a doctor. If you do visit a doctor and your symptoms are mild, you may be given a delayed prescription to collect antibiotics if your symptoms start getting worse, or do not improve.⁶

If you do decide to wait and see if things settle down, you can try taking painkillers like paracetamol and ibuprofen, and you are encouraged to keep well hydrated. Drinking plenty of water is easier said than done when you have a UTI, as there is a temptation to drink less seeing as you will be feeling the urge to pee all the time. However, good levels of hydration do help to fight the infection.⁷

Currently, guidelines advise that even women with uncomplicated UTIs are offered antibiotics. However, if you only have mild symptoms, you can try waiting for up to 48 hours to see if the infection settles down by itself

Being well hydrated is important in any infection, to maintain good circulation and allow the body to fight the infection adequately. There has been some thought in the past that perhaps drinking enough could completely flush out bacteria from the urinary tract; studies haven’t really been able to show that drinking plenty of fluids alone can get rid of an infection, but the amount of bacteria present can be dramatically reduced if a person is well hydrated, and therefore regularly passing urine.⁸ Although many people say drinking cranberry juice can help, this isn’t currently recommended as part of treatment for UTIs.

Should your symptoms be causing you distress, or you find they don’t disappear, or even worsen, after 48 hours, you should go and see a doctor, who will prescribe antibiotics if a UTI is confirmed. There are lots of different antibiotics used to treat UTIs, and again this choice can depend on whether you have a complicated UTI or not.⁹

Which antibiotic will I be prescribed?

Uncomplicated UTIs are most commonly treated with a three day course of one of two antibiotics: trimethoprim or nitrofurantoin. Trimethoprim works by stopping certain enzymes in bacteria from working, which stops the bacteria from being able to multiply.¹⁰ Nitrofurantoin works slightly differently — it damages a bacteria’s DNA to stop it from being able to work properly.

Occasionally, the course of antibiotics you are given won’t work for you. This might be because the UTI is caused by an unusual bacteria, because the bacteria are resistant to the antibiotic you’ve been given, or that the symptoms are caused by something else entirely.

If symptoms remain significant after the three day course of antibiotics, it is advisable to return to your GP; they might do more tests to ensure the diagnosis of UTI is definitely correct

Generally, when you visit a healthcare professional with symptoms suggestive of a UTI, urine will be tested in what’s called a “dipstick test” — this is a fast test which can show whether certain cells and components which may indicate infection are present in the urine. If this test is positive and symptoms are suggestive of a UTI, the urine sample probably won’t be sent off to the labs for further testing, as there is no real need for this.¹¹

What if my symptoms remain after I’ve taken antibiotics?

If symptoms remain significant after the three day course of antibiotics, it is advisable to return to your GP; they might do more tests to ensure the diagnosis of UTI is definitely correct, for example, they may send off your urine sample.

Alternatively, they may have initially sent a urine sample and the results may be back within three days. This would allow them to choose a different antibiotic which may work better for the specific bacteria causing that particular infection.

While it isn’t always necessary to take a urine sample when you originally visit the doctor with symptoms, this may be requested if you return with worsening symptoms after three days.

What symptoms will I notice if my UTI involves the kidneys?

Some symptoms associated with UTIs can imply that the infection involves the kidneys. In this instance, the infection is considered more serious, is classed as a complicated UTI as mentioned above, and always requires medical advice.

Symptoms of pyelonephritis (an infection in the kidneys) include having a fever or chills, having pain around the sides or the back, and feeling or being sick. If you think you have a UTI and are also experiencing these symptoms, you should see a doctor as soon as possible.

Symptoms of pyelonephritis (an infection in the kidneys) include having a fever or chills, having pain around the sides or the back, and feeling or being sick

All complicated UTIs generally require antibiotic treatment, although unfortunately some even require a hospital stay. Other UTIs which require medical attention are those which occur in children, in cisgender men, and in people who are pregnant.¹²

Urine samples should be sent for further testing in the case of complicated UTIs, to ensure that if the symptoms don’t get better, other antibiotics can be found and tried.

Could my UTI symptoms be a sign of anything else?

Sometimes symptoms can be mistaken for a UTI but actually be caused by something else. For example, pain, burning, and stinging when passing urine can also be a sign of chlamydia, so it is important to exclude this if you are at risk.¹³

Needing to pass urine very frequently may also be a sign of other conditions, such as type 1 diabetes, although this is much less common than UTIs. However, it may be considered if other symptoms are present, like feeling thirsty very often.

Other less common conditions can also cause an increase in the frequency of passing urine, including a high blood level of calcium, and some medications. Blood in the urine can be a sign of lots of things other than a UTI, including kidney stones, STIs, and problems with the anatomy of the urinary tract. An examination from a medical professional and common tests if necessary can help distinguish between a UTI and another cause.

Generally speaking, UTIs are very treatable and won’t always need antibiotics — it just depends on the severity of your symptoms. However, if you experience symptoms and are unsure, it is always best to visit your doctor to be on the safe side, as some types of UTIs always need antibiotics.

Featured image is of a spilled bottle of pills against an orange background

Last updated October 2023
Next update due 2026