Triprim (trimethoprim): insights on usage and interactions
Triprim (trimethoprim), like the other broad spectrum antibiotics, is used to treat harmful bacteria. This antibiotic particularly targets a variety of bacteria, causing conditions like urinary tract infections.
However, it’s important to be careful with how it’s used to prevent resistance from developing. Learn more about the drug, from its mechanism of action to potential side effects, and understand how it works.
In this article
1. How does Triprim (trimethoprim) work?
Triprim (trimethoprim) is designed to combat bacterial illness and infections but not viruses like the common cold or flu. It does so by targeting certain aspects of bacterial metabolism.
Specifically, it can help stop bacteria from making an important form of folic acid called tetrahydrofolate, which they need to build DNA, RNA, and proteins. This method blocks bacteria, including many types of gram-positive and gram-negative bacteria, from growing and multiplying.
Sometimes bacteria can become resistant to trimethoprim by changing their genetic makeup. This can happen when mutations occur in the enzyme that trimethoprim targets, making it less affected by the drug’s effects. This is why doctors may ask you to be careful when using trimethoprim – to avoid bacteria becoming resistant to it.
Despite this, Triprim (trimethoprim) is primarily used as an infection treatment for conditions like urinary tract infections (UTI). Notably, the safety of trimethoprim during pregnancy has yet to be fully established, underscoring the need for cautious use.[1]
2. How do you take Triprim (trimethoprim)?
Your antibiotic dose depends on your health condition and how well you’re responding to treatment. For children, their weight is important for figuring out the right dose.
You can take Triprim (trimethoprim) with or without food, usually once or twice a day, precisely as your doctor advises. If you’re using the liquid form, ensure accurate dosing by using a special measuring device or spoon.
If you forget to take a dose of this antibiotic medication, take it as soon as you remember. If it’s almost time for your next dose, skip the missed one. Never double up on doses.
It’s vital to finish the entire course of the antibiotic therapy prescribed by your doctor to fully eliminate the infection, even if you feel better before it’s finished.
3. Who can take Triprim (trimethoprim)?
For chronic urinary tract infections, a common Triprim dosage is 100 mg once daily. This regimen can be used for long-term prophylaxis over several months to manage and reduce the recurrence of infections.[2]
For the treatment of UTIs, this antibiotic is typically considered for adult patients. However, it’s associated with an increased risk of acute kidney injury and hyperkalemia, especially in individuals with underlying conditions or those taking certain medications like renin-angiotensin system blockers.[3]
Before starting to take this prescribed medication, it’s crucial to discuss your complete medical history, any allergies you might have, the current medications you’re taking, and your pregnancy status with your doctor. This way, they can assess the benefits and risks before starting treatment.
4. Side effects of Triprim (trimethoprim)
Common side effects of taking Triprim (trimethoprim) can include an upset stomach, vomiting, diarrhea, rashes (which may include itching or mild discomfort), and headaches. These are generally mild and may resolve as your body adjusts to the medication.
However, there are rare but serious side effects to be vigilant about. If you experience any of the following symptoms, immediately seek help from your doctor:
- Severe stomach pain
- Watery or bloody diarrhea (which can occur even months after your last dose)
- A change in skin colour to pale, grey, or bluish tones
- Fever
- Unusual weakness
- A sore or swollen tongue
- Easy bruising
- Purple or red spots under the skin
Additionally, one of the recognised side effects of Triprim (trimethoprim) is hyperkalemia, which is an elevated level of potassium in the blood. This condition has been observed with both high and standard doses of trimethoprim.
The drug can reduce renal potassium excretion, mimicking the effects of potassium-sparing diuretics. Those at increased risk include individuals with higher doses, underlying renal impairment, or those on treatments that impair renal potassium excretion.[4]
5. Triprim (trimethoprim) and other medications
Trimethoprim, found in medications like Resprim Forte (trimethoprim and sulfamethoxazole) and Alprim (trimethoprim), has been identified as an inhibitor of several key proteins involved in drug metabolism and transport, such as MATE1, OCT1, OCT2, and CYP2C8.
This means that it can change how other medications like metformin, repaglinide, and pioglitazone work. It’s also a ‘victim’ drug in interactions with rifampicin, which can affect trimethoprim’s processing and impact its effectiveness.[5]
6. Medicines you should not use with Triprim (trimethoprim)
Combining Triprim (trimethoprim) with certain medications can increase the risk of adverse effects or diminish the effectiveness of the drugs. Anticoagulants like warfarin could have their effects enhanced, increasing bleeding risks.
Trimethoprim can also raise levels of digoxin and phenytoin, risking toxicity. It may impact the effectiveness of diabetes medications such as repaglinide or pioglitazone. Furthermore, oral typhoid vaccines might not work if taken with trimethoprim. You should consult with your doctor about all medications before starting trimethoprim.
7. How to order home delivery of Triprim (trimethoprim) with Chemist2U
Use our online platform for an easy way to get your medications delivered directly to you. Simply download our app or go to our website to upload your escript. Once done, a Chemist2U partner pharmacist in your area will carefully prepare your medications.
You’ll also find a variety of over-the-counter medication and general pharmacy products available for purchase, allowing you to shop for everything you need just as if you were at a physical pharmacy, but online.
For those in metro and major regional areas across Australia, we offer same-day delivery straight from the chemist to your doorstep for orders received before the cutoff time (typically 2.00 p.m., but may vary in some locations). This ensures your health needs are met promptly.
However, we go beyond just delivering medications. We’re here to ensure you always have your important medication when you need it.
At Chemist2U, we’re making medication easy. Have your medication home delivered by Chemist2U today!
References
[1] https://pubmed.ncbi.nlm.nih.gov/6985448/ ↑
[2] https://pubmed.ncbi.nlm.nih.gov/7100825/ ↑
[3] https://pubmed.ncbi.nlm.nih.gov/29438980/ ↑
[4] https://pubmed.ncbi.nlm.nih.gov/10738846/ ↑
[5] https://pubmed.ncbi.nlm.nih.gov/33182761/ ↑
