Medication features:

  • Treats bacterial infection that causes cystitis
  • Taken in tablet form
  • An antibiotic


Available strengths:

200 mg


Price £17.99

Includes free private prescriptions

In stock

Delivery Time


Expected delivery date:

Wednesday, 13 December 2023

If you order within:


Next Day Delivery

Next Day

Quick Assessment


UK Registered Pharmacy

UK Registered

Discreet & Confidential

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  • Overview
  • FAQ
  • Side Effects
  • Patient Information Leaflet
  • Reviews

What is Trimethoprim

Urinary tract infections can be uncomfortable and inconvenient. If left untreated, they can also be dangerous. Trimethoprim is a drug that is used in the prevention and cure of these infections. It is a type of a synthetic antibiotic and it has been included on the World Health Organisation’s list of essential medicines.

Why choose Trimethoprim?

Trimethoprim is especially potent in targeting cystitis, which is a common type of bacterial infection that can cause a range of potentially distressing symptoms, including pain when you pass urine, a frequent need to urinate, dark and strong-smelling urine, and pain during sexual intercourse. It can also leave you feeling generally achy, tired, sick and unwell. In addition, if left unchecked, there is a risk that cystitis can lead to a potentially serious kidney infections. It is, therefore, advisable to address these urinary tract infections quickly before they are able to develop. Trimethoprim is an effective and speedy treatment option that can help you to fight infections in this part of your body.

What dose should I choose?

The treatment comes in tablet form, and usually one tablet is taken twice a day. However, additional doses may sometimes be required. If you complete an online consultation on our website, our specialist medical team can recommend the best dosage for you. You can also get more information on this topic by contacting your doctor or speaking to one of our healthcare experts.

How should I take Trimethoprim?

You can take Trimethoprim on an empty stomach or with a meal. For the best results, you should aim to take the tablets at the same times each day.

How does Trimethoprim work?

The drug is referred to as a bacteriostatic antibiotic, and it works by inhibiting the DNA synthesis of bacteria by reducing levels of tetrahydrofolic acid. This process serves to prevent the multiplication and spread of bacteria, eventually killing them off. The treatment should clear your infection up after a couple of days. If it doesn’t, you may need to seek further medical advice.

What are the side effects of Trimethoprim?

There are a number of potential side effects connected with taking Trimethoprim. For example, it can lead to nausea, vomiting, diarrhoea, loss of appetite, abnormal taste, trouble sleeping and an allergic rash. If you’re concerned about any of these possible ill effects or you’d simply like further information on this antibiotic, don’t hesitate to get in touch with our medical specialists by phone or email.

Why can't I take Trimethoprim if I am lactose intolerant?

No. You can not take Trimethoprim if you are lactose intolerant because all Trimethoprim tablets contain lactose.

Can I take Trimethoprim if I am pregnant?

Trimethoprim is known to have an impact on the folic acid metabolism of the body. That is how it functions as an antibiotic. However, folic acid is an essential aspect of the development of a foetus. Due to this, it is crucial to avoid taking this medicine during pregnancy. In particular, it should be avoided during the first trimester when the foetal spinal cord is developing.

Why should I alternate the antibiotics for my cystitis?

There are antibiotic-resistant bacteria present in the body. For example, with cystitis, the bacteria tend to be more resistant to Trimethoprim than Nitrofurantoin. So, when you are taking repeated courses of antibiotics to treat urine infections, it is crucial to alternate the antibiotics to help reduce the development of resistance.

Why take Trimethoprim at night before bed?

Taking Trimethoprim at night before bed is crucial when treating a condition like cystitis. This is because taking this medicine before going to sleep allows it to stay in the bladder for a more extended period of time. This is where the medicine is effective, so it will help you clear the infection quicker.

Trimethoprim Alternatives

Besides Trimethoprim, various other antibiotics are commonly used to treat UTIs. Macrobid and the generic version of Macrobid, known as Nitrofurantoin, are also available as treatments for UTIs.

For other symptoms of cystitis, you can turn towards over-the-counter remedies. For instance, you can take OTC painkillers such as ibuprofen and paracetamol for relief from inflammation and pain due to UTIs.

Trimethoprim vs Nitrofurantoin

Similar to Trimethoprim, Nitrofurantoin is an antibiotic commonly used to treat UTIs that occur due to bacteria. However, Trimethoprim is also used to treat kidney and ear infections, while Nitrofurantoin is not.

Nitrofurantoin and Trimethoprim share a few common side effects, such as nausea, sickness, headache, as well as mild diarrhoea. On the other hand, Nitrofurantoin can also cause excessive flatulence.

Similarly, Trimethoprim and Nitrofurantoin are usually taken over the span of three to seven days to treat a UTI. Trimethoprim is found in 100 mg and 200 mg tablets, while Nitrofurantoin comes in 50 mg or 100 mg tablets or capsules.

In essence, the two treatments have the same tolerance, effect, and side effects. Therefore, there is little difference between them. However, the choice between the two depends on personal preference.

Trimethoprim vs Macrobid

Macrobid is the brand name for Nitrofurantoin in the UK. It works precisely like Nitrofurantoin and has the same features. There is no difference between Trimethoprim and Macrobid as they contain the same active ingredients. The choice between the two depends on personal preference.

Trimethoprim and Macrobid are well-tolerated and have the same level of efficacy.

Can You Buy Trimethoprim Over the Counter?

No. You can not purchase Trimethoprim without a prescription in the UK. It is a prescription-only medicine.

In case you do not have a prescription for Trimethoprim and require one as soon as possible, go to our homepage and fill out the free questionnaire. The questionnaire will contain a few questions regarding your health, which an on-site expert will review. Once your case is approved, you will be issued a prescription. With this, you can place an order for Trimethoprim without any complications.

Can I drink alcohol while using Trimethoprim Tablets?

It is safe to drink alcohol while using Trimethoprim Tablets.

Can pregnant or breastfeeding women use Trimethoprim Tablets?

Trimethoprim Tablets are suitable for use by pregnant and breastfeeding women.

Can I take Trimethoprim Tablets on an empty stomach?

Trimethoprim Tablets can be taken with or without food. However to prevent nausea like side effects it is advised to take Trimethoprim Tablets after consuming a well balanced and healthy meal.

How should I take Trimethoprim Tablets?

You should swallow one whole tablet of Trimethoprim Tablets with a drink of water. This tablet should not be broken, chewed or crushed.

What if I forget to take my dose of Trimethoprim Tablets?

If you forget to take your dose of Trimethoprim Tablets you should take them as soon as you remember, unless it is almost time for your next dose. If it is almost time for your next dose you should skip the dose you just missed and continue as normal. You should never take two doses at once, even if you are making up for a missed dose.

Can I combine other drugs with Trimethoprim Tablets?

There are a few drugs which you must not combine with Trimethoprim Tablets, they include the following:

  • Rifampicin
  • Repaglinide
  • Pioglitazone
  • Phenytoin
  • Digoxin
  • Warfarin

Does using Trimethoprim Tablets affect my contraception?

Using Trimethoprim Tablets doesn’t directly affect one’s contraception. However if after using Trimethoprim Tablets you experience diarrhoea, your combined pill may be ineffective.

Like all medicines, after using Trimethoprim Tablets you are likely to experience a number of different side effects. Common side effects and how to overcome them include the following:

  • Itching: use an antihistamine which will reduce the itching
  • Feeling sick: take Trimethoprim Tablets after consuming a well balanced meal
  • Diarrhoea: drink lots of water to prevent dehydration
  • Headaches: rest and drink lots of water to ensure you are hydrated

Always read the patient information leaflet before starting your treatment. The patient information can be found here.

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