Buy Trimethoprim online with free consultation & prescription

Book a quick face-to-face video consultation with a certified prescribing pharmacist, nurse, or doctor. If approved, your Trimethoprim will be prescribed* and delivered straight to your door with tracked delivery and customs duties paid. No hidden fees. No delays. Just expert care.

Trimethoprim is indicated for the treatment of Cystitis.

*Includes Free Private Prescription & Consultation.

Manufactured by Athlone.

Trimethoprim packaging which is available to order online from NowPatient with free next day delivery

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Trimethoprim

Trimethoprim doses and pack sizes

100mg, 28 Tablets200mg, 14 Tablets

*Your clinician will recommend the right strength and quantity for you during the consultation.

Treatment$21.58

Shipping & import duties$20.00

Total if approved$41.58

How it works

Fast, simple booking with a certified prescribing clinician

If approved, get your treatment prescription

Get tracked delivery straight to your door

No hidden fees. No delays.

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Trimethoprim alternatives

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From $31.30

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Trimethoprim prices

Brand/Generic	Form	Dosage	Quantity	Price	Delivery Cost	Consultation Cost
TrimethoprimGeneric	Tablets	100mg	28	$21.58	$0.00*(with Core+ Plan)	$0.00
TrimethoprimGeneric	Tablets	200mg	14	$31.30	$0.00*(with Core+ Plan)	$0.00

Key facts about Trimethoprim

Updated on October 19, 2026

Proloprim

About Trimethoprim

Trimethoprim is an antibacterial agent used for the treatment of bacterial infections, cystitis and urinary tract infections (UTIs). Trimethoprim stops bacterial dihydrofolate reductase, an enzyme that helps with the formation of tetrahydrofolic acid, preventing the production of bacterial DNA. Trimethoprim may be used alone or with sulfamethoxazole (co-trimoxazole) for the treatment and/or prophylaxis of UTIs.

NowPatient offers Trimethoprim as a treatment for cystitis only, following an online consultation with a prescribing clinician.

Key facts of Trimethoprim

Trimethoprim is an antimicrobial used to treat bacterial infections, cystitis and UTIs
Trimethoprim can be taken up to 3 days
Trimethoprim has some common side effects which include nausea and vomiting
It can be dangerous if you take Trimethoprim with certain medications. If you’re not sure if it is safe, discuss this with the prescribing clinician

Who is Trimethoprim not suitable for?

Trimethoprim may not be suitable for some people. To make sure it’s safe for you, speak to the prescribing clinician before taking Trimethoprim if you:

Are allergic to Trimethoprim
Have liver or kidney disease
Have high blood potassium levels (hyperkalemia)
Have galactose intolerance, glucose-galactose malabsorption, or total lactase deficiency
Have anemia or folate deficiency (low folic acid in your blood)
Have porphyria or any other blood disorder
Are pregnant or trying to get pregnant

How and where to get Trimethoprim?

You can buy Trimethoprim safely and securely from NowPatient. You can start a consultation today for free and if you qualify for treatment, you only pay for the cost of the medication. Delivery is made to your home or office from our registered pharmacy.

Our service is certified, safe and effective, and we only ever treat conditions. If you book a consultation with a prescribing clinician for the treatment of cystitis, you can discuss if Trimethoprim is a suitable treatment option for you.

At the end of the consultation, the clinician will decide if a treatment plan is suitable for you. If it is, the clinician will issue you with a prescription which can then be ordered, paid for and delivered directly to your chosen address by NowPatient.

Dosage and strength for Trimethoprim for Cystitis

Trimethoprim is available in tablet form when used for cystitis. It is available in strengths ranging from 100 mg to 200 mg.

Information about how to take Trimethoprim tablets for Cystitis

Trimethoprim 200mg tablets should be taken twice daily (every 12 hours) until the prescribed course is complete. It is normally a 3-day course for uncomplicated cystitis, but can be prescribed as a 7-day course.

If you have blood in your urine, have back pain, fever, chills, vomiting, or have had cystitis more than three times in one year you should see your primary care provider as soon as possible.

What happens if you take too much Trimethoprim?

If you take more than prescribed, then it can lead to some unpleasant side effects. You should talk to your doctor or reach out to one of our prescribing clinicians, if you have taken too much Trimethoprim and you experience any of the following side effects:

What are the side effects of Trimethoprim?

Side effects of Trimethoprim are split into common and serious.

Common side effects include:

Nausea, vomiting, diarrhea, and skin rash

If you experience any serious adverse effects, you should contact your doctor or an urgent care center.

If you experience a serious allergic reaction with the signs shown below you should contact emergency services on 911.

Your lips, mouth, throat or tongue suddenly become swollen
You’re breathing very fast or struggling to breathe (you may become very wheezy or feel like you’re choking or gasping for air)
Your throat feels tight or you’re struggling to swallow
Your skin, tongue or lips turn blue, grey or pale (if you have black or brown skin, this may be easier to see on the palms of your hands or soles of your feet)
You suddenly become very confused, drowsy or dizzy
Someone faints and cannot be woken up

Always report adverse effects to the FDA MedWatch reporting system. You can read more about this here How and where do I report side effects of my medication? – NowPatient

Information about taking Trimethoprim at the same time as other medications or herbal supplements

There is not enough evidence to suggest there are any drug interactions between herbal supplements and Trimethoprim. In any event, you should let your prescribing clinician know if you are taking any herbal supplements or other prescription drugs, such as:

ACE inhibitors
Azathioprine
Cyclosporin
Digoxin
Methotrexate
Phenytoin
Repaglinide
Rifampicin
Warfarin, heparin

Why might Trimethoprim not work for Cystitis?

Trimethoprim may not work for you. A common reason may include aquired Trimethoprim resistance.

Can Trimethoprim taken for Cystitis be taken long term?

Taking a 3-day course of Trimethoprim should clear most bladder and urinary tract infections. If your symptoms have not cleared once you have completed your course of Trimethoprim, speak to your doctor for medical advice.

Is there a herbal Trimethoprim?

No. Herbal Trimethoprim does not exist. If you have been marketed such a formulation, it may be fake.

Can women use Trimethoprim?

Women can take Trimethoprim for the treatment of cystitis. However, Trimethoprim should not be used during pregnancy and only under the guidance of your doctor when breastfeeding.

Should I avoid any particular food or drink when taking Trimethoprim?

You can eat and drink normally when taking Trimethoprim.

What lifestyle changes can I make to help me with Cystitis?

You may modify your lifestyle in a number of ways, and this may have a positive impact on your cystitis. Drink plenty of water when suffering from cystitis to flush bacteria through your system and to help keep hydrated to prevent cystitis from recurring. Also, wipe from front to back when you go to the toilet, to prevent infection.

Alternatives to Trimethoprim

Alternatives for the treatment of cystitis include nitrofurantoin, quinolones, or amoxicillin.

Sources

Medical Disclaimer

NowPatient has taken all reasonable steps to ensure that all material is factually accurate, complete, and current. However, the knowledge and experience of a qualified healthcare professional should always be sought after instead of using the information on this page. Before taking any drug, you should always speak to your doctor or another qualified healthcare provider.

The information provided here about medications is subject to change and is not meant to include all uses, precautions, warnings, directions, drug interactions, allergic reactions, or negative effects. The absence of warnings or other information for a particular medication does not imply that the medication or medication combination is appropriate for all patients or for all possible purposes.

FAQs

Answers to popular questions about Trimethoprim

What is Trimethoprim?

Trimethoprim is an antibiotic used primarily to treat urinary tract infections (UTIs). It is available as 100 mg and 200 mg tablets and as a liquid suspension. Trimethoprim is a first-line treatment for uncomplicated lower UTIs (cystitis) recommended by clinical guidelines. It is a prescription-only medicine in the UK, although it may be supplied by pharmacists under state pharmacist prescribing protocols for uncomplicated UTIs in women.

How does Trimethoprim work?

Trimethoprim is a dihydrofolate reductase inhibitor — it blocks an enzyme essential for bacterial DNA synthesis. By preventing bacteria from making the nucleotides needed for DNA replication, trimethoprim stops bacteria from multiplying and kills them. It achieves high concentrations in the urine, making it particularly effective for UTIs. It is effective against most common UTI pathogens including E. coli.

What is the difference between Trimethoprim and Nitrofurantoin?

Both are first-line antibiotics for uncomplicated UTIs. Trimethoprim is taken twice daily for 3 days and does not need to be taken with food. Nitrofurantoin (Macrobid) is also taken twice daily for 3 days but should be taken with food. E. coli resistance to trimethoprim in the UK is approximately 30% in some areas, compared to under 5% for nitrofurantoin. Your prescriber may choose based on local resistance patterns and your medical history.

What is the usual dose of Trimethoprim for a UTI?

For acute uncomplicated UTI: 200 mg twice daily for 3 days (women) or 7 days (men). For UTI prophylaxis (recurrent UTIs): 100 mg once daily at night for 3–6 months. Trimethoprim can be taken with or without food. Drink plenty of water during treatment to help flush out the infection.

How quickly does Trimethoprim work?

Most women notice an improvement in UTI symptoms within 24–48 hours of starting trimethoprim. Complete the full 3-day course even if symptoms improve, to ensure the infection is fully treated. If symptoms have not improved after 48 hours or worsen, contact your prescriber as the bacteria may be resistant to trimethoprim.

What are the side effects of Trimethoprim?

Common side effects include nausea, diarrhea, headache, and rash. Trimethoprim can occasionally cause hyperkalaemia (raised potassium levels), particularly in patients taking ACE inhibitors, ARBs, or potassium-sparing diuretics. Very rarely, it can cause blood disorders (pancytopenia, megaloblastic anaemia due to folate antagonism). If you develop a rash, sore throat, fever, or mouth ulcers, stop trimethoprim and seek medical advice.

What medications interact with Trimethoprim?

Trimethoprim can increase the effect of warfarin — INR should be monitored. It can increase potassium levels when combined with ACE inhibitors, ARBs, or spironolactone. It increases methotrexate levels and toxicity — this combination should be avoided. Trimethoprim can also increase the blood levels of some drugs cleared by the kidneys, including digoxin and lamivudine.

Can I take Trimethoprim during pregnancy?

Trimethoprim should be avoided in the first trimester of pregnancy because it is a folate antagonist and may theoretically increase the risk of neural tube defects. If a UTI antibiotic is needed in the first trimester, nitrofurantoin or cefalexin are preferred. Trimethoprim can be used in the second and third trimesters if the benefit outweighs the risk. It should not be used at term if nitrofurantoin is also contraindicated.

Can I drink alcohol with Trimethoprim?

There is no specific drug interaction between trimethoprim and alcohol. However, alcohol can irritate the bladder and worsen UTI symptoms. It is sensible to limit alcohol while treating a UTI and to stay well-hydrated with water.

How can I get Trimethoprim?

You can request Trimethoprim through NowPatient by completing a short online consultation with one of our prescribing clinicians. Your clinician will assess your symptoms to confirm whether you have an uncomplicated urinary tract infection and whether Trimethoprim is suitable for you. If you have a fever, back or side pain, or are pregnant, seek prompt medical advice. If treatment is suitable, a prescription is issued and your medication is dispensed by our registered pharmacy and delivered to your door.

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