Question 1

How long does it take for Trimethoprim to work for a UTI?

Accepted Answer

You should start to feel symptom relief within 24 to 48 hours of starting the course. However, it is crucial to complete the entire course of antibiotics as prescribed by your doctor, even if you feel better, to ensure the infection is completely cleared and to prevent recurrence or resistance.

Question 2

Can I drink alcohol while taking Trimethoprim?

Accepted Answer

It is generally advised to avoid alcohol while taking any antibiotics, including Trimethoprim. While there is no direct 'disulfiram-like' reaction (severe nausea and vomiting) known with Trimethoprim, alcohol can exacerbate some side effects like nausea and dizziness and may place additional stress on your liver, which is processing the medication. It's best to err on the side of caution until you have finished your course.

Question 3

Why might Trimethoprim not be working for my UTI?

Accepted Answer

If your symptoms are not improving after 2-3 days, or if they are getting worse, you should contact your doctor. The bacteria causing your infection may be resistant to Trimethoprim. This is why a urine test is sometimes needed to confirm the type of bacteria and the most effective antibiotic to treat it. Your doctor can then prescribe an alternative medication.

Question 4

Is Trimethoprim the same as Amoxicillin or Nitrofurantoin?

Accepted Answer

No, they are different classes of antibiotics. Amoxicillin is a penicillin, Nitrofurantoin is a nitrofuran antibiotic, and Trimethoprim is a diaminopyrimidine. They all work in different ways to kill bacteria. The choice of antibiotic depends on the specific bacteria causing the infection, local resistance patterns, and patient factors like allergies. They are not interchangeable.

Question 5

Does Trimethoprim cause tiredness or fatigue?

Accepted Answer

Fatigue is an uncommon side effect but can occur. If you experience severe tiredness, especially with pale skin or shortness of breath, it may indicate anaemia (rare) – consult your doctor.

Question 6

Can I take paracetamol or ibuprofen with Trimethoprim?

Accepted Answer

Yes, paracetamol and ibuprofen are generally safe to take with Trimethoprim for pain or fever. However, if you have kidney problems, consult your doctor before taking ibuprofen.

Question 7

How should I store Trimethoprim tablets?

Accepted Answer

Store below 25°C in a dry place, away from moisture and direct sunlight. Keep the tablets in their original blister pack or container. Do not use after the expiry date.

Question 8

Can Trimethoprim affect contraception?

Accepted Answer

Trimethoprim does not directly affect hormonal contraception (the pill). However, if you experience vomiting or severe diarrhoea as a side effect, this may reduce absorption of oral contraceptives. Use additional barrier methods during such episodes.

Question 9

Is Trimethoprim safe for people with sulfa allergy?

Accepted Answer

Trimethoprim is a sulfonamide derivative. People with a known allergy to sulfa drugs should not take Trimethoprim due to risk of cross-reaction.

Question 10

Can I take Trimethoprim if I am breastfeeding?

Accepted Answer

Trimethoprim passes into breast milk in small amounts. It is usually considered compatible with breastfeeding, but you should consult your doctor before use, especially if the infant is premature or has glucose-6-phosphate dehydrogenase (G6PD) deficiency.

Question 11

What should I do if I miss a dose of Trimethoprim?

Accepted Answer

Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose. Do not take a double dose to make up for a forgotten one.

Question 12

Can children take Trimethoprim?

Accepted Answer

Trimethoprim can be used in children over 6 years for acute UTIs (100mg twice daily) and over 12 years for prophylaxis (100mg at night). For children under 6, a liquid formulation may be prescribed by a specialist.

Question 13

Does Trimethoprim interact with warfarin?

Accepted Answer

Yes, Trimethoprim can increase the effect of warfarin, leading to an increased risk of bleeding. If you take warfarin, your doctor will monitor your INR closely and may adjust your warfarin dose.

Product Name	Trimethoprim
Manufacturer	Accord Healthcare Limited
Active Ingredient	Trimethoprim
Administration	Oral tablet
Presentation	White, flat bevelled-edge tablets
Available Strengths	200mg / 6 Tablets
Product Type	POM — Prescription Only
Starting Price	£22.99
Suitable for pregnancy?	Do not use
Use with alcohol	Avoid
Link to Patient Information Leaflet	Trimethoprim PIL ↗

Trimethoprim Tablets

Trimethoprim Treatment