Trimethoprim
Buy trimethoprim 200mg treatment for cystitis online from Dr Fox - for recurring infection. Be prepared with a standby antibiotic to keep for when needed.
Start orderBuy trimethoprim online in UK
How to order trimethoprim online for UK delivery:
- Read medical information about cystitis treatment
- Answer medical questions to check for eligibility
- Reviewed by doctors - posted from UK pharmacy (tracked 24hr service)
Prices
Cystitis treatment | Quantity | Cost |
---|---|---|
Trimethoprim 200mg | 6 tablets (1 course - in stock) | £8.90 |
Price match guarantee
Prescription issued online - small prescription fee per order.
Compare prices: Dr Fox prices are 25%-50% lower cost than other online clinics.
Prescription fees
Dr Fox supplies medicine on prescription and charges a small prescription fee based on the order value of each prescription.
Prescriptions are issued by our doctors online and sent electronically to our pharmacy.
Order value | Prescription fee |
---|---|
up to £10 | £1.00 |
up to £20 | £2.00 |
up to £40 | £3.00 |
over £40 | £4.00 |
If you have your own private paper prescription please post to our pharmacy (details).
Dr Fox prices are 25%–50% lower than other UK online clinics.
Items | Dr Fox | UK Meds | Superdrug | Oxford Online Pharmacy | Lloyds |
---|---|---|---|---|---|
Trimethoprim 200mg x 6 | £8.90 | £14.99 | £25.00 | £19.99 | £23.99 |
UK delivery | £2.90 | £4.95 | included | £2.95 | included |
Delivery charges
UK delivery only: £2.90 per consultation via Royal Mail 24 Signed For (1-3 working days with tracking).
Parcel forwarding services are not permitted. Use only UK home or work delivery address.
Returns and refunds - unwanted items can be returned within 14 working days for a full refund.
About trimethoprim
- Trimethoprim is a prescription-only antibiotic tablet mainly used to treat cystitis in women and other urinary infections.
- Take 200mg twice daily for 3 days with 12 hours between doses.
- Order in advance as a standby treatment for repeated episodes.
- Read the patient leaflet for a full list of side effects, cautions, and interactions with other drugs.
Choosing the right antibiotic for cystitis
The information below is about trimethoprim tablets. There is a separate page about nitrofurantoin capsules, the alternative antibiotic available from Dr Fox for cystitis in women. General information about cystitis and standby treatment, and selecting the right antibiotic, can be found at the cystitis medical information page. Please also read the manufacturer's patient information leaflet supplied with trimethoprim tablets.
Trimethoprim is an antibiotic commonly used to treat uncomplicated cystitis in women, and other urine infections. In the last few years antibiotic resistance to trimethoprim has increased. About 30% of the bacteria which cause cystitis are now resistant to trimethoprim and it is no longer always the first choice antibiotic by GPs. The antibiotic nitrofurantoin is now often more effective and is often the first choice, although trimethoprim is still widely prescribed and many women find it effective and prefer it.
For further information see NHS - trimethoprim.
Taking trimethoprim
Trimethoprim 200mg twice daily for 3 days (12 hours between doses) is usually effective for cystitis. The tablets should be swallowed whole with a glass of water. They should not be chewed.
Improvement is usually seen within 24 hours and symptoms are usually completely resolved after 3 days.
Cautions and contraindications
Trimethoprim is not suitable for everyone. Patients with some medical conditions or who are also taking some other medicines cannot take it. Checks for suitability are carried out in the online consultation which is part of the ordering process.
Do not take trimethoprim tablets if the following apply:
- Allergy to trimethoprim or to any of the other tablet ingredients.
- You are pregnant.
- Severe liver problems.
Do not take trimethoprim tablets without first checking with your doctor or pharmacist if the following apply:
- Kidney problems, including dialysis.
- Low folic acid which may lead to anaemia.
- Known risk of high blood potassium levels.
- Porphyria.
Interactions
Trimethoprim should not be taken with the following medicines:
- Repaglinide (diabetes).
- Procainamide (heart rhythm control).
- Digoxin (heart).
- Diuretics (water tablets).
- Rifampicin (tuberculosis).
- Warfarin-type anticoagulants (blood thinners requiring regular blood testing).
- Phenytoin (epilepsy).
- Pyrimethamine and dapsone (malaria).
- Immunosuppressant and bone marrow depressant drugs (including azathioprine, methotrexate, ciclosporin).
- Colistimethate (cystic fibrosis).
If in doubt about other medication check with your own doctor or pharmacist.
Side effects and severe reactions
As with any medicine side effects may occur although most patients do not experience them, or they may be mild and treatment does not always need to be stopped.
Allergic reactions
In very rare cases (fewer than 1 in 10,000), there may be an acute allergic reaction leading to angioedema or anaphylaxis. If affected, stop taking trimethoprim, and contact your GP, out-of-hours service, or telephone 111 or see 111.nhs.uk online. In an emergency telephone 999.
Side effects (non-emergency)
The side effects listed below are not medical emergencies, but may require medical advice.
Common (may affect up to 1 in 10 people):
- Feeling sick (nausea), being sick, diarrhoea.
- Headache.
- Skin rashes including hives (urticaria) and itching.
- Thrush or sore mouth (glossitis).
For more details about side effects see the manufacturer's patient information leaflet.
Pregnancy and breastfeeding
DO NOT take trimethoprim tablets if you are pregnant, think you may be pregnant or are trying to get pregnant.
If you are breastfeeding, it is usually fine to take a short course of trimethoprim, although small amounts are found in breast milk. The manufacturer recommends asking your doctor or pharmacist for advice before taking trimethoprim when breastfeeding.
Dr Fox does not supply cystitis treatment for women who are pregnant or breastfeeding - please contact your GP.
Other measures which can help cystitis
- Increase the amount of water you are drinking each day to 2-3 litres (4-5 pints, or 10-12 glasses or mugs).
- Avoid alcohol, caffeine, and fizzy drinks which can irritate the bladder.
- Take paracetamol or ibuprofen for pain if necessary.
Sometimes cystitis will go away by itself in a few days without antibiotic treatment. If symptoms are mild, self-treatment and 'wait-and-see' for a few days may be the best approach. If symptoms are severe, or worsening, antibiotics are usually preferred. Women who have repeated infections will usually know if their symptoms are likely to stop on their own.
Patient Information Leaflet

The Patient Information Leaflet (PIL) is the leaflet included in the pack with a medicine and must be read before taking the medicine. It is written for patients and gives information about taking or using a medicine.
Trimethoprim FAQs
Can I take trimethoprim if I am lactose intolerant?
Unfortunately no. Trimethoprim tablets all contain lactose.
Why can't I take trimethoprim now I'm pregnant?
Trimethoprim affects folic acid metabolism, and this is how it works as an antibiotic. Folic acid is very important in the development of the foetus. It is therefore recommended to avoid trimethoprim during pregnancy, particularly in the first trimester when the foetal spinal cord is developing.
Why should I alternate the antibiotics for my cystitis?
Antibiotic resistant bacteria are becoming more common. If taking repeated courses of antibiotics to treat repeat urine infections, using a different antibiotic each time reduces development of resistance. It is also more likely to be effective if there is some resistance to the alternate antibiotic.

Authored 18 February 2010 by Dr Tony Steele
MB ChB Sheffield University 1983. Former hospital doctor and GP.
Reviewed by Dr A. Wood, Dr C. Pugh, Dr B. Babor, Dr P. Hunt
Last reviewed 06 December 2021
Last updated 7 December 2021
References
- Accord Healthcare, 2019, Trimethoprim 200mg Tablets: Summary of Product Characteristics, accessed 06 December 2021
- BNF/NICE, 2017, TRIMETHOPRIM, accessed 06 December 2021
Product reviews
Trimethoprim rated 4.93/5 in 189 product reviews
See over 35,000 service reviews of Dr Fox
Very quick delivery
13/05/2022 14:20
Anonymous Verified
Excellent friendly and quick service
08/05/2022 00:43
S. Booth Verified
This works for me but sometimes I need more than 3 days course
13/04/2022 18:34
Anonymous Verified
Brilliant really helped
10/04/2022 19:43
D. Knight Verified
Works well
11/02/2022 12:57
Anonymous Verified
The order process
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