Specifically, the Food and Drug Administration (FDA) has approved sulfamethoxazole/trimethoprim oral tablet to treat the following bacterial infections in adults and some children:
Sulfamethoxazole/trimethoprim oral tablet is also approved to treat the following bacterial infections in adults:
This article describes possible side effects of sulfamethoxazole/trimethoprim oral tablet. You’ll also find information on cost savings and coupon options for sulfamethoxazole/trimethoprim. You can explore this overview article to learn more about sulfamethoxazole/trimethoprim oral tablet, including the drug’s uses, side effects, ways to save on cost, and more.
Sulfamethoxazole/trimethoprim oral tablet is a generic version of the brand-name drugs Bactrim and Septra. Sulfamethoxazole/trimethoprim also comes in other oral forms and an injectable form, but these forms aren’t described in this article. To learn more about these forms, talk with your doctor.
More common side effects of sulfamethoxazole/trimethoprim
Sulfamethoxazole/trimethoprim oral tablet may cause mild or serious side effects. Below are some of the more common side effects of this medication.
Commonly reported side effects of sulfamethoxazole/trimethoprim oral tablet include:
- vomiting
- loss of appetite
- mild skin rash
- itchy skin
- nausea*
* To learn more about this side effect, see the “Side effects of sulfamethoxazole/trimethoprim in detail” section below.
Mild side effects of sulfamethoxazole/trimethoprim
Sulfamethoxazole/trimethoprim may cause certain mild side effects. Usually, mild side effects are temporary and can be easily managed. Tell your doctor or pharmacist if you have side effects that don’t go away or become bothersome.
Mild side effects of sulfamethoxazole/trimethoprim oral tablet that occurred in studies include:
- vomiting
- loss of appetite
- mild skin rash
- itchy skin
- abdominal pain
- joint or muscle pain
- cough
- fatigue (low energy)
- nausea*
- mild allergic reaction*†
* To learn more about this side effect, see the “Side effects of sulfamethoxazole/trimethoprim in detail” section below.
† An allergic reaction is possible with sulfamethoxazole/trimethoprim oral tablet. But it’s unclear whether it occurred in the drug’s studies.
Sulfamethoxazole/trimethoprim oral tablet may cause more mild side effects than those listed above. For details, see the drug’s prescribing information.
Serious side effects of sulfamethoxazole/trimethoprim
Sulfamethoxazole/trimethoprim may cause certain serious side effects. If you have any serious side effects from sulfamethoxazole/trimethoprim oral tablet, call your doctor right away. But if you think you’re having a medical emergency or your side effects feel life threatening, take immediate action. Call 911 or a local emergency number, or go to the nearest emergency room.
After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. Visit MedWatch’s website if you’d like to notify the FDA about a side effect you’ve had with sulfamethoxazole/trimethoprim.
Serious side effects of sulfamethoxazole/trimethoprim oral tablet that occurred in studies include:
- very low blood sugar
- high blood potassium level
- low blood sodium level
- lung damage
- low red blood cell levels
- low white blood cell levels
- low platelet levels
- liver problems, including hepatitis
- kidney failure
- hallucinations
- muscle damage
- hypothyroidism
- irregular heart rhythm, such as QT prolongation
- Clostridioides difficile–associated diarrhea*
- serious skin reactions, such as Stevens-Johnson syndrome *
- severe allergic reaction*†
* To learn more about this side effect, see the “Side effects of sulfamethoxazole/trimethoprim in detail” section below.
† An allergic reaction is possible with sulfamethoxazole/trimethoprim oral tablet. But it’s unclear whether it occurred in the drug’s studies.
Common questions about side effects of sulfamethoxazole/trimethoprim
Here are answers to some common questions about the side effects of sulfamethoxazole/trimethoprim oral tablet. If you have other questions, talk with your doctor or pharmacist.
How long do side effects of sulfamethoxazole/trimethoprim typically last?
Most common side effects of sulfamethoxazole/trimethoprim oral tablet go away after a few days of starting treatment or after you stop taking the medication.
In rare cases, some side effects may last longer.*
Talk with your doctor if you have bothersome side effects from sulfamethoxazole/trimethoprim.
* For more details on the long-term side effects of sulfamethoxazole/trimethoprim tablets, see the question below.
Does sulfamethoxazole/trimethoprim cause long-term side effects?
Yes, in some cases sulfamethoxazole/trimethoprim oral tablet may cause long-term side effects. These can last for a while after you’ve stopped taking the drug.
Examples of long-term side effects reported with sulfamethoxazole/trimethoprim oral tablet include:
- liver problems, including hepatitis
- serious skin reactions, such as Stevens-Johnson syndrome*
- Clostridioides difficile-associated diarrhea*
Talk with your doctor to learn more about these side effects and how to manage them. Ask your doctor for more information about how long these side effects of sulfamethoxazole/trimethoprim may last.
* To learn more about this side effect, see the “Side effects of sulfamethoxazole/trimethoprim in detail” section below.
Coupon for sulfamethoxazole/trimethoprim
Visit this page to access Optum Perks coupons and get price estimates for sulfamethoxazole/trimethoprim when you use the coupons. These coupons can provide significant savings on your prescription costs.
Note: Optum Perks coupons cannot be used with insurance copays or benefits.
Side effects of sulfamethoxazole/trimethoprim in detail
Below you’ll find details on some of the side effects of sulfamethoxazole/trimethoprim oral tablet.
Clostridioides difficile–associated diarrhea
In studies, Clostridioides difficile–associated diarrhea (CDAD) was rare in people taking sulfamethoxazole/trimethoprim oral tablet. This side effect may be mild or severe.
With CDAD, you have an overgrowth of the bacterium called Clostridioides difficile (also called C. diff). This happens because taking oral antibiotics, including sulfamethoxazole/trimethoprim, can disrupt the balance of bacteria that typically live in your digestive tract. This can lead to an overgrowth of C. diff., which produces toxins that can cause diarrhea.
Symptoms of CDAD may include:
- fever
- nausea
- abdominal pain or cramping
- bloody stool
Certain factors can increase the risk of CDAD with sulfamethoxazole/trimethoprim oral tablet. These include taking this medication long-term and being hospitalized for a long time.
Ways to manage
If you experience symptoms of CDAD, tell your doctor. They’ll likely test your stool to determine if you have CDAD. If they confirm that you have CDAD, they’ll likely have you stop taking sulfamethoxazole/trimethoprim. They may prescribe other antibiotics to treat CDAD.
It’s also important to drink plenty of fluids while you recover from CDAD. Having diarrhea can lead to dehydration (low fluid level), and increasing your fluid intake can help prevent this.
Serious skin reactions, such as Stevens-Johnson syndrome
In studies, serious skin reactions, such as Stevens-Johnson syndrome, were rare in people taking sulfamethoxazole/trimethoprim oral tablet. This side effect may be serious and is usually related to an allergic reaction* to the medication.
With Stevens-Johnson syndrome, you have a blistering rash that typically starts on your face and chest. The rash may also spread to the inside of your nose, mouth, and eyes.
Symptoms that may accompany the rash or start a few days before may include:
- fever
- sore throat
- red eyes
- muscle aches
Certain factors can increase the risk of Stevens-Johnson syndrome with sulfamethoxazole/trimethoprim oral tablet. These include having HIV or a weakened immune system.
* See the “Allergic reaction” section below to learn more.
Ways to manage
Stevens-Johnson syndrome is a medical emergency. If you experience symptoms of Stevens-Johnson syndrome, call 911 or go to a local emergency department right away. Let the emergency care team know all the medications you take. They’ll likely have you stop taking sulfamethoxazole/trimethoprim.
You will need to be admitted to the hospital to receive treatment for symptoms of Stevens-Johnson syndrome.
Free prescription coupons
Seriously … free. Explore prices that beat the competition 70% of the time.
Get free cardNausea
In studies, nausea was common in people taking sulfamethoxazole/trimethoprim oral tablet. This side effect is usually mild.
With nausea, you experience a desire to vomit. Symptoms may include stomach pain or discomfort and dry heaving.
Certain factors can increase the risk of nausea with sulfamethoxazole/trimethoprim oral tablet. These include taking this medication on an empty stomach.
Ways to manage
Having a snack or a small meal before taking your sulfamethoxazole/trimethoprim dose may help prevent nausea with this medication. It might also be helpful to have small, frequent meals throughout the day and avoid spicy or greasy foods during your sulfamethoxazole/trimethoprim treatment.
If you have concerns about nausea while taking this medication, tell your doctor. They may recommend over-the-counter or prescription medications to help you feel less nauseous.
Allergic reaction
For some people, sulfamethoxazole/trimethoprim oral tablet can cause an allergic reaction.
Symptoms can be mild or serious, and they may include:
- itchiness
- skin rash
- swelling under the skin, usually affecting eyelids, lips, hands, or feet
- swelling of the mouth, tongue, or throat, which can make it hard to breathe
- flushing (temporary warmth, redness, or deepening of skin color)
In rare cases, serious allergic reactions with sulfamethoxazole/trimethoprim may include severe skin reactions, such as:
- toxic epidermal necrolysis
- drug rash with eosinophilia and systemic symptoms
- acute febrile neutrophilic dermatosis
- Stevens-Johnson syndrome*
* See the “Serious skin reactions, such as Stevens-Johnson syndrome” section above to learn more.
Ways to manage
For mild allergic reaction symptoms, such as a mild rash, call your doctor right away. They may recommend treatments to help manage your symptoms. They’ll also let you know whether you should keep taking the medication.
For severe allergic reaction symptoms, such as swelling, trouble breathing, or a severe skin reaction, call 911 or your local emergency number right away. These symptoms require immediate medical care because they can become life threatening. If you’ve had a serious allergic reaction to sulfamethoxazole/trimethoprim oral tablet, your doctor may recommend taking a different medication instead.
Warnings for sulfamethoxazole/trimethoprim
Below are some factors you may want to discuss with your doctor before taking sulfamethoxazole/trimethoprim oral tablet.
Warnings
It may not be safe for you to take sulfamethoxazole/trimethoprim oral tablet if you have specific health conditions. These are sometimes called drug-condition interactions. Other things may also affect whether sulfamethoxazole/trimethoprim oral tablet is a safe treatment option for you.
Before taking sulfamethoxazole/trimethoprim oral tablet, tell your doctor about your health and medications you take. Things to consider include:
- kidney problems
- liver problems
- alcohol use disorder
- being 65 years or older
- porphyria
- thyroid problems
- AIDS
- G6PD deficiency
- high blood potassium level
- low blood sodium level
- past allergic reaction to sulfamethoxazole/trimethoprim
Sulfamethoxazole/trimethoprim and pregnancy
Sulfamethoxazole/trimethoprim oral tablet should not be taken during pregnancy. If you’re planning a pregnancy or can become pregnant, talk with your doctor before taking this medication. Your doctor may suggest birth control options to use during treatment with sulfamethoxazole/trimethoprim.
Sulfamethoxazole/trimethoprim and breastfeeding
It’s not known whether sulfamethoxazole/trimethoprim oral tablet should be taken while breastfeeding. Sulfamethoxazole/trimethoprim passes into breast milk, and it’s not safe for children younger than 2 months of age. If you’re currently breastfeeding or planning to do so, talk with your doctor before taking this medication.
Sulfamethoxazole/trimethoprim and alcohol
Sulfamethoxazole/trimethoprim oral tablet is not known to interact with alcohol.
But taking sulfamethoxazole/trimethoprim and drinking large amounts of alcohol for a long time can cause a certain type of anemia (low level of red blood cells). Taking this medication if you have been drinking large amounts of alcohol for a while can increase your risk of this side effect.
If you drink alcohol, talk with your doctor about whether it’s safe to consume it during your treatment with sulfamethoxazole/trimethoprim oral tablet.
What to ask your doctor
This article describes common and serious side effects of sulfamethoxazole/trimethoprim oral tablet. If your doctor prescribes this medication, they can discuss possible side effects with you. Let your doctor know if you have concerns or questions about treatment with this medication.
Here’s a list of some possible questions you may want to ask your doctor:
- Does having diabetes increase my risk of side effects with sulfamethoxazole/trimethoprim?
- Is my risk of Clostridioides difficile-associated diarrhea higher if I’m taking this medication to treat traveler’s diarrhea or shigellosis?
- Is my risk of side effects lower if I take a lower dose of sulfamethoxazole/trimethoprim?
Disclaimer: Optum Perks has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.