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Trimethoprim is an antibiotic that is used for the treatment of Urinary Tract Infections. It can treat cystitis and other mild to moderate UTIs in females.

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Jordan Christchurch reviewed
"Fast, easy to use and very responsive customer service. Prices are also very competitive."
RJ Layton reviewed
"5 Start service is so much easier than going to my local pharmacy, especially when feeling under the weather."
Bianca Carthright reviewed
"No fuss, and fast delivery. Welzo dispatched my order the same day and it arrived in the morning."
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What is Trimethoprim?

Trimethoprim is a medication that can be effectively used to treat cystitis in women and other urinary tract infections (UTIs). A urinary tract infection is caused due to bacterial infection. This inflammation then results in cystitis. 

How does it work?

Trimethoprim works by entering the bladder and working on the affected area of bacterial infection. It kills the bacteria and prevents them from proliferating. It then effectively treats the existing infection.

Is Trimethoprim right for me?

If you are experiencing discomfort while urinating or facing an increased urge to urinate, you could have a Urinary Tract Infection. Trimethoprim can treat mild UTIs.

The product images shown may represent the range of products, or be for illustration purposes only and may not be an exact representation of the product.

Side Effects

All medications can cause potential side effects, here are some commonly reported side effects:

  • Headache
  • Stomach discomfort
  • Thrush
  • Irritation to Skin or Rashes
  • Vomiting

Disclaimer: This website does not constitute medical advice, you should also consult with a doctor before taking medication. If you experience any major reactions to any medication you are taking, you must seek immediate medical attention.


Next Day Delivery Guarantee

All orders placed before 14:00 on weekdays will be delivered the next working day. For the majority of the UK, medication will be dispatched by Royal Mail, Monday to Friday, if ordered before 14:00. Dispatches are sent using Royal Mail's Next-Day Tracked 24-Hour service. We will email you tracking information directly and you should receive your order the day after dispatch.

Our Discreet Packaging Promise

We know that many of our customers turn to us when they need personal medication, preferring to use our online service rather than shopping for the product face to face. That is why our delivery is always discreetly packaged in plain brown boxes or envelopes. You will not have to worry about any content descriptions, and the package will be for your eyes only!


Potential and Commonly Used Dosage Guidelines for Trimethoprim

One tablet swallowed whole with water, twice a day for three days, started at the onset of symptoms.

Disclaimer: This website does not provide medical advice. No information listed on this website is intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider with any questions you may have regarding a medical condition or treatment before undergoing a new health care regimen, and never disregard professional medical advice or delay in seeking it because of something you have read on this website.

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A medical professional will review your answers to the online medical consultation and determine if it’s safe to prescribe and what treatments are available.

Can I drink alcohol while taking Trimethoprim?

It is generally recommended that you avoid drinking alcohol while taking Trimethoprim or any other antibiotic. Alcohol can increase the risk of side effects from Trimethoprim, such as dizziness, headache, and nausea. Drinking alcohol can also make it more difficult for your body to fight off infection. If you do choose to drink alcohol while taking Trimethoprim, it is important to drink in moderation and to stay hydrated.

When should you take Trimethoprim?

Trimethoprim should be taken as prescribed by your healthcare provider. It is typically taken twice a day, with or without food. If you have trouble swallowing pills, Trimethoprim can be crushed and mixed with water. It is important to take Trimethoprim at evenly spaced intervals to maintain a constant level of medication in your body. Missing doses of Trimethoprim can increase your risk of developing resistance to the medication.

Is this medication suitable for me?

Please get in touch with a doctor if you are unsure what medication is suitable for you. You can also complete our online consultation form to check your eligibility for the product.

How is the medication delivered?

All orders placed before 14:00 from Monday to Friday will be dispatched that day. The orders are sent using 24 Hour Tracked delivery provided by Royal Mail. Items will usually arrive the very next day after the order has been placed. We also provide tracking for your orders to check the status and location of your parcel. All our medication is packaged in plain confidential padded white or brown envelopes. This ensures that your orders are discreet, and the content of the orders will be for your eyes only.

Is Trimethoprim a strong antibiotic?

Trimethoprim is a moderate-strength antibiotic. It is not as strong as some other antibiotics, but it is still effective against many types of bacteria. Trimethoprim should only be used to treat infections that are caused by bacteria. It should not be used to treat viral infections such as the common cold or flu.

Is Trimethoprim a penicillin drug?

No, Trimethoprim is not a penicillin drug. It is an antibiotic that belongs to a class of drugs called sulphonamides. Sulphonamides act by inhibiting the synthesis of folic acid, which is required for the development of bacteria and other microorganisms. Trimethoprim is used to treat infections caused by bacteria. It is also used to prevent the development of Pneumocystis carinii pneumonia (PCP) in people with AIDS. PCP is a serious lung infection that can be fatal. Trimethoprim should not be used to treat viral infections such as the common cold or flu.

How do I order my medication?

Some products only require an online consultation which approximately takes 1 minute to complete, enabling you to then buy the product. Other products will also require a prescription; in this case, you will need to complete the online consultation, and then one of our partner pharmacy prescribers or doctors will review the online consultation questions and approve the order for delivery if you are eligible to purchase the item.

Can I cancel or return my order?

For non-medicinal products, you are eligible to return the product within 14 days of receipt in the same packaging you received. For medicinal products, you are eligible to cancel the order only until it has been dispatched. From that point forward, you are no longer eligible to return the order.

You have the right to cancel your order for medication up to the point when your medication is dispatched.

Why Welzo
Discreet next day shipping
Discreet next day shipping

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Trusted UK Pharmacy

Welzo only works with UK-based pharmacies. All our medication is authentic and issued by GPhC-registered pharmacies and prescribers.

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Supportive & Caring

Our team of clinicians and health experts can support you along every step of your treatment journey.

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