- Bacterial Infections 101 Pictures Slideshow
- Take the Tummy Trouble Quiz
- Hepatitis C Slideshow Pictures
- What is sulfamethoxazole, and how does it work (mechanism of action)?
- Is sulfamethoxazole available as a generic drug?
- Do I need a prescription for sulfamethoxazole?
- What are the side effects of sulfamethoxazole?
- What is the dosage for sulfamethoxazole?
- Which drugs or supplements interact with sulfamethoxazole?
- Is sulfamethoxazole safe to take if I'm pregnant or breastfeeding?
- What else should I know about sulfamethoxazole?
What is sulfamethoxazole, and how does it work (mechanism of action)?
Sulfamethoxazole is an anti- bacterial sulfonamide. It prevents the formation of dihydrofolic acid, a compound that bacteria must be able to make in order to survive. Although it was once a very useful antibiotic, it is almost obsolete as a single agent today due to the development of bacterial resistance to its effects. Sulfamethoxazole is now used primarily in combination with trimethoprim, a combination product known as Bactrim or Septra. Sulfamethoxazole was approved by the FDA in 1961. According to the FDA database, all brand and generic formulations of sulfamethoxazole have been discontinued.
What are the side effects of sulfamethoxazole?
: Common side effects of sulfamethoxazole are:
Sulfamethoxazole should be stopped at the first appearance of a skin rash since the rash may become severe. Serious rashes include Stevens-Johnson syndrome (aching joints and muscles; redness, blistering, and peeling of the skin); toxic epidermal necrolysis (difficulty in swallowing; peeling, redness, loosening, and blistering of the skin). Sulfamethoxazole therapy also can cause extensive sunburn, following exposure to sunlight. Patients receiving sulfamethoxazole should avoid excessive exposure to sunlight and should wear sunscreen.
Other important rare side effects include:
Sulfamethoxazole may form crystals in the urine which may damage the kidney and cause bleeding into the urine. It is important to drink additional liquids during sulfonamide therapy to prevent these side effects.
Quick GuideSymptoms of Mono: Infectious Mononucleosis Treatment
What is the dosage for sulfamethoxazole?
Sulfamethoxazole usually is taken two or three times daily, with or without meals. It should be taken with 6 to 8 ounces of liquid to prevent crystals from forming in the urine. Persons with advanced kidney diseases may require lower doses.
Which drugs or supplements interact with sulfamethoxazole?
Sulfamethoxazole can enhance the blood-thinning effects of warfarin (Coumadin), possibly leading to bleeding. Sulfonamides such as sulfamethoxazole can increase the metabolism (break-down and elimination) of cyclosporine (causing loss of effectiveness of cyclosporine), and can add to the kidney damage caused by cyclosporine. All sulfonamides can crystallize in urine when the urine is acidic. Since methenamine (Hiprex, Urex, Mandelamine) causes an acidic urine, it should not be used with sulfonamides.
Is sulfamethoxazole safe to take if I'm pregnant or breastfeeding?
The effects of the sulfonamide class of antibiotics on the fetus have not been adequately studied. Therefore, physicians may use them if the benefits are deemed to outweigh potential risks. On the other hand, use of sulfonamides near term (that is, near the ninth month of pregnancy) may cause bilirubin to be displaced from proteins in the infant's blood. Displacement of bilirubin can lead to a dangerous condition called kernicterus in which the bilirubin damages the brain. For this reason, sulfonamides should not be used near term birth.
What else should I know about sulfamethoxazole?
What preparations of sulfamethoxazole are available?
Tablets: 500 mg and 1 gm.
How should I keep sulfamethoxazole stored?
The tablets should be kept at room temperature, 15 C - 30 C (59 F - 86 F).
Reference: FDA Prescribing Information
Quick GuideSymptoms of Mono: Infectious Mononucleosis Treatment
Sulfamethoxazole (Gantanol, Gantanol DS) is an antibiotic prescribed for the treatment of malaria, pinkeye due to chlamydia, toxoplasmosis, and urinary tract infections. According to the FDA database, all brand and generic formulations of sulfamethoxazole have been discontinued. Side effects, drug interactions, warnings and precautions, and patient safety information should be reviewed prior to taking any medication.
Multimedia: Slideshows, Images & Quizzes
MRSA Quiz: Infection Symptoms & Treatment
It's the MRSA Quiz! For the carriers among us, you'd be surprised that the infectious superbug is lurking on this body part! Take...
Do I Have Pneumonia? Symptoms & Signs
Pneumonia can be deadly. Take the Pneumonia Quiz on MedicineNet to learn more about this highly contagious, infectious disease....
Picture of Bacterial Conjunctivitis (Pink Eye)
Pink eye, or conjunctivitis, is redness and inflammation of the membranes (conjuctiva) covering the whites of the eyes and the...
Related Disease Conditions
Malaria is a disease that is spread by the bite of an infected Anopheles mosquito. Malaria symptoms include fever, chills,...
Pinkeye, also called conjunctivitis, is redness or irritation of the conjunctivae, the membranes on the inner part of the eyelids...
Sexually Transmitted Diseases in Women (STD)
Sexually transmitted diseases, or STDs, are infections that are transmitted during any type of sexual exposure, including...
Urinary Tract Infections (UTIs)
A urinary tract infection (UTI) is an infection of the bladder, kidneys, ureters, or urethra. E. coli, a type of bacteria that...
Whooping Cough (Pertussis)
Whooping cough (pertussis) is highly contagious respiratory infection that is caused by the bacteria Bordetella pertussis. There...
Chlamydia in Women (Symptoms and Cures)
Chlamydia is the most common sexually transmitted disease in the U.S. Signs and symptoms of chlamydia, a bacterial infection,...
Toxoplasmosis (toxo) is a parasitic infection that causes flulike symptoms, swollen lymph nodes, and muscle aches and pains that...
STDs in Men
Sexually transmitted diseases (STDs) are infections transmitted during sexual contact. They may be caused by viruses, bacteria,...
Treatment & Diagnosis
- Pneumonia FAQs
- MRSA FAQs
- How To Reduce Your Medication Costs
- Pharmacy Visit, How To Get The Most Out of Your Visit
- Indications for Drugs: Approved vs. Non-approved
- Generic Drugs, Are They as Good as Brand-Names?
- Drugs: Buying Prescription Drugs Online Safely
- Medication Disposal - What to Do with Old or Unusable Medication
- Dangers of Mixing Medications
- Drugs: The Most Common Medication Errors
Medications & Supplements
Prevention & Wellness
Daily Health News
Infectious Disease Resources
Subscribe to MedicineNet's General Health Newsletter
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Top sulfamethoxazole Related ArticlesComplete List
Pink Eye PicturePink eye, or conjunctivitis, is redness and inflammation of the membranes (conjuctiva) covering the whites of the eyes and the membranes on the inner part of the eyelids. See a picture of Pink Eye and learn more about the health topic.
Chlamydia in Women OverviewChlamydia is the most common sexually transmitted disease in the U.S. Signs and symptoms of chlamydia, a bacterial infection, include vaginal discharge, abdominal pain, burning with urination, blood in the urine, and feelings of urinary urgency and frequency. Untreated chlamydia can cause pelvic inflammatory disease (PID), increased risk of ectopic pregnancy, and infertility. Chlamydia is diagnosed with a culture or by identification of the genetic material of the bacteria. Treatment of chlamydia consists of a course of antibiotics.
Drug InteractionsDrug interactions occur frequently. Get facts about the types of drug interactions, what substances or other things that may interact with drugs such as OTC drug and prescription drugs, vitamins, food(s) (grapefruit), and laboratory tests. Find out how to protect yourself from potential drug interactions.
Drugs: What You Should Know About Your DrugsImportant information about your drugs should be reviewed prior to taking any prescription drug. Side effects, drug interactions, warnings and precauctions, dosage, what the drug is used for, what to do if you miss a dose, how the drug is to be stored, and generic vs. brand names.
Liver Blood TestsAn initial step in detecting liver damage is a simple blood test to determine the presence of certain liver enzymes in the blood. Under normal circumstances, these enzymes reside within the cells of the liver. But when the liver is injured, these enzymes are spilled into the blood stream, and can lead to diseases like fatty liver, type 2 diabetes, obesity, and hepatitis. Several medications also can increase liver enzyme test results.
Malaria FactsMalaria is a disease that is spread by the bite of an infected Anopheles mosquito. Malaria symptoms include fever, chills, nausea, vomiting, and body aches. Treatment involves supportive care and antibiotics.
Take the MRSA Quiz!It's the MRSA Quiz! For the carriers among us, you'd be surprised that the infectious superbug is lurking on this body part! Take the quiz and learn how to keep this Staph infection at bay.
PertussisWhooping cough (pertussis) is highly contagious respiratory infection that is caused by the bacteria Bordetella pertussis. There are an estimated 300,000 plus deaths annually from whooping cough (pertussis). Whooping cough commonly affects infants and young children but can be prevented with immunization with the vaccine. First stage whooping cough symptoms are a runny nose, sneezing, low-grade fever, a mild cough with the cough gradually becoming more severe. After one to two weeks, the second stage of whooping cough begins.
Pink EyePinkeye, also called conjunctivitis, is redness or irritation of the conjunctivae, the membranes on the inner part of the eyelids and the membranes covering the whites of the eyes. These membranes react to a wide range of bacteria, viruses, allergy-provoking agents, irritants, and toxic agents.
Do I Have Pneumonia?Pneumonia can be deadly. Take the Pneumonia Quiz on MedicineNet to learn more about this highly contagious, infectious disease.
Sexually Transmitted Diseases (STDs In Women)
Sexually transmitted diseases, or STDs, are infections that are transmitted during any type of sexual exposure, including intercourse (vaginal or anal), oral sex, and the sharing of sexual devices, such as vibrators. Women can contract all of the STDs, but may have no symptoms, or have different symptoms than men do. Common STDs in women are:
- Zika virus
- Genital herpes
- Hepatitis B
- Hepatitis C
- Pubic lice
- Genital warts
Treatment for STDs depends upon the type.
STDs in Men Overview
Sexually transmitted diseases (STDs) are infections transmitted during sexual contact. They may be caused by viruses, bacteria, or parasites. STDs in men cause no symptoms or symptoms like
- rashes, or
Common STDs in men include:
- Hepatitis B
- Hepatitis C
- Genital warts
- Genital herpes
Some STDs in men are treatable while others are not. STDs are diagnosed with tests that identify proteins or genetic material of the organisms causing the infection. The prognosis of an STD depends on whether the infection is treatable or not. Use of latex condoms can help reduce the risk of contracting an STD but it does not eliminate the risk entirely.
sulfonamides-oralSulfonamides are a class of drugs from a sulfur-containing chemical (sulfanilamide). Examples of sulfonamides include sulfamethoxazole/trimethoprim (Bactrim, Bactrim DS, Co-trimoxazole, Septra, Septra DS, Cotrim, SMZ-TMP, SMZ-TMP DS, Sulfatrim); sulfasalazine (Azulfidine, Sulfazine); and sulfisoxazole (Truxazole, Gantrisin). Some of these drugs are available only in generic forms. Side effects of sulfonamides may include dizziness, lethargy, diarrhea, nausea, vomiting, headache, serious skin rashes and anorexia. Sulfonamides are not recommended for women who are pregnant or breastfeeding. Side effects and drug interactions should be reviewed prior to taking this medication.
ToxoplasmosisToxoplasmosis (toxo) is a parasitic infection that causes flulike symptoms, swollen lymph nodes, and muscle aches and pains that may last from a few days to several weeks. Toxoplasmosis can be contracted by touching the hands to the mouth after gardening, cleaning a cat's litter box, or anything that came into contact with cat feces. Toxoplasmosis can also be contracted by eating raw or partly cooked meat, especially pork or lamb, or touching the hands to the mouth after contact with raw or undercooked meat.
Urinary Tract InfectionA urinary tract infection (UTI) is an infection of the bladder, kidneys, ureters, or urethra. E. coli, a type of bacteria that lives in the bowel and near the anus, causes most UTIs. UTI symptoms include pain, abdominal pain, mild fever, urinary urgency and frequency. Treatment involves a course of antibiotics.