Is Bactrim An Effective Treatment For Prostatitis?

Bactrim is an antibiotic commonly prescribed for treating prostatitis. 

It contains one part of trimethoprim with five parts of sulfamethoxazole. 

Trimethoprim helps prevent bacterial resistance to sulfamethoxazole, making it much more potent. 

Bactrim is also used to treat urinary tract infections, ear and throat infections, some respiratory tract infections, travelers diarrhea, and some rare infections.

Is Bactrim effective in treating prostatitis?

Generally, Bactrim is considered quite effective for treating bacterial prostatitis. However, prostatitis can be challenging to treat, and it often comes back after you stop taking antibiotics. 

The chronicity of prostatitis is one of the reasons why many doctors prefer using Bactrim.

Bactrim is considered safe for extended use under the supervision of a healthcare provider., and it can help with urinary tract and bladder infections, which often go hand in hand with prostatitis.

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Treating prostatitis can be challenging because it isn’t always caused by infections.

Usually, doctors use antibiotics like Bactrim after lab tests confirm a bacterial infection. 

However, in some cases where there are clear signs of a bacterial infection, like a fever or a sudden worsening of chronic prostatitis, doctors might recommend starting Bactrim right away.

When lab tests are possible, doctors will try to identify the infectious agent and its sensitivity to the antibiotic for prostatitis. 

There are many available antibiotics for prostatitis, and doctors will choose the one they think is best for the infection.

Dosage of Sulfamethoxazole/Trimethoprim for prostatitis

The most common dosage of Bactrim is 400 mg sulfamethoxazole and 80 mg trimethoprim, taken twice a day.

However, in most instances of prostatitis, doctors prefer a double dose, also known as Bactrim DS (double strength). 

Bactrim DS contains 800 mg sulfamethoxazole and 160 mg trimethoprim, taken twice a day.

How long does Bactrim take to cure prostatitis?

How long it takes to treat prostatitis with Bactrim varies among patients.

Some patients may benefit from two weeks of antibiotic therapy, and others may need longer. 

Studies show that doctors would prescribe Bactrim for at least two weeks to treat prostatitis. However, other experts think that this is insufficient, and antibiotic therapy should continue for three to four weeks.

Bactrim is a prescription drug and should be used as long as prescribed by your doctor. 

Remember to take antibiotics as prescribed since not doing so increases the risk of antibiotic resistance.

prostate healer

Warnings and allergies to Bactrim

Taking Bactrim is generally considered safe, but it can cause some side effects. Allergies to Bactrim are extremely common, which might show up as skin rashes.

In rare cases, it can cause more serious allergic reactions.

Using Bactrim for a long time, like when treating prostatitis, could lead to anemia, stomach problems, and even kidney issues, although this is quite rare. 

It may also cause folate deficiency. Some rare problems include psychiatric problems, hormonal imbalances, and muscle pains.

Signs Bactrim is working

Signs that Sulfamethoxazole/Trimethoprim is working usually show up within a few days to a week of starting the drug. 

You might notice less urgency and frequency when you need to pee, reduced pelvic pain, and an overall improvement in prostatitis symptoms, like fever and chills.

Your doctor can also check your urine for white blood cells and bacteria. If they find fewer white blood cells and no bacteria causing prostatitis, that’s a good sign that Bactrim is working. 

But remember, always finish the full course of antibiotics as prescribed by your healthcare provider to make sure the infection is fully cleared.


Bactrim is one of the oldest and relatively safest antibiotics still in use. 

Sulfamethoxazole/Trimethoprim is still an antibiotic of choice to treat certain infections like UTIs, prostatitis medical treatment, and specific respiratory infections. 

What is good about this antibiotic is that it is generally good for prolonged antibacterial therapy. However, allergic reactions to the drug are unfortunately pretty common.

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  1. National Institutes of Health (NIH) [Internet]. 2015. How Sulfa Drugs Work.
  2. US FDA. BACTRIMTM sulfamethoxazole and trimethoprim DS- Poduct Label [Internet]. 2013.
  3. Stevermer JJ, Easley SK. Treatment of Prostatitis. afp. 2000 May 15;61(10):3015–22. 
  4. McGuire EJ, Lytton B. Bacterial prostatitis Treatment with trimethoprim-sulfamethoxazole. Urology. 1976 May 1;7(5):499–500. 
  5. Bjerklund Johansen TE, Grüneberg RN, Guibert J, Hofstetter A, Lobel B, Naber KG, et al. The role of antibiotics in the treatment of chronic prostatitis: a consensus statement. Eur Urol. 1998 Dec;34(6):457–66. 
  6. Kuiper SG, Ploeger M, Wilms EB, van Dijk MM, Leegwater E, Huis in’t Veld RAG, et al. Ceftriaxone for the Treatment of Chronic Bacterial Prostatitis: A Case Series and Literature Review. Antibiotics. 2022 Jan;11(1):83.

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