We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is Trimethoprim?

Mary McMahon
Updated May 17, 2024
Our promise to you
WiseGEEK is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At WiseGEEK, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Trimethoprim is an antibiotic medication a doctor may prescribe for the treatment or prevention of bacterial infection. This medication is bacteriostatic in nature, working by blocking key biological functions in the bacteria to halt their growth and proliferation. Eventually, they will die because they are no longer able to access nutrients necessary for cell function. Manufacturers produce trimethoprim tablets in a variety of dosages and the medication is usually taken at home.

Urinary tract infections, pneumonia, and bacterial infections leading to diarrhea can all respond to trimethoprim. In a patient with a history of recurrent urinary tract infections, this medication may be used as prophylaxis to prevent infections, in which case the patient can take the medication in the long term, rather than in a short therapeutic course. A doctor may also prescribe trimethoprim for other reasons.

The most common trimethoprim side effects are nausea, diarrhea, and vomiting. Patients can also develop headaches, fatigue, and oral sores. These side effects are more serious, and a patient should discuss them with a doctor. The doctor may recommend a change in dosage or take the patient off the medication to prevent further complications. Patients with low-level gastrointestinal side effects should take note of any changes and report them to a doctor.

A course of trimethoprim may last for varying lengths of time, depending on the infection and the doctor's recommendations. It is important to complete the course of medication and to attend a follow-up appointment so the doctor can check to see if the infection is still present. If the patient's infection is still active, it may be necessary to go back on the trimethoprim or to switch to a different medication. The doctor may consider culturing a sample from the patient and testing for antibiotic susceptibility to see if the bacteria are resistant.

Antibiotics can sometimes interfere with each other. Unless a doctor specifically recommends it, a patient should not take multiple antibiotic drugs. Patients on antibiotics may also find other medications less effective. When a doctor prescribes trimethoprim, patients should ask about specific drug interactions to determine if they are at risk of an adverse drug reaction. It may be necessary to take special precautions or temporarily change a drug regimen while on antibiotics. The patient's pharmacist should also keep a complete list of the medications a patient takes, and if there is a question about a prescription, the pharmacist can bring it up with the doctor.

WiseGEEK is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Mary McMahon
By Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a WiseGEEK researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.

Discussion Comments

Mary McMahon

Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a...

Read more
WiseGEEK, in your inbox

Our latest articles, guides, and more, delivered daily.

WiseGEEK, in your inbox

Our latest articles, guides, and more, delivered daily.