Delaine's General Health Blog: sulfamethoxazole and trimethoprim, Bactrim, Septra

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GENERIC NAMES: Sulfamethoxazole and trimethoprim; cotrimoxazole

BRAND NAMES: Bactrim, Bactrim DS, Septra, Septra DS

DRUG CLASS AND MECHANISM: Bactrim is a combination of two synthetic (man-made) antibiotics, sulfamethoxazole and trimethoprim. Both drugs reduce the ability of some bacteria to utilize folic acid for growing. Sulfamethoxazole is an anti-bacterial sulfonamide, a "sulfa" drug. It disrupts the production of dihydrofolic acid while trimethoprim disrupts the production of tetrahydrofolic acid. Dihydrofolic acid and tetrahydrofolic acid are forms of folic acid that bacteria and human cells use for producing proteins. Trimethoprim inhibits production of tetrahydrofolic acid by inhibiting the enzyme responsible for making tetrahydrofolic acid from dihydrofolic acid. By combining both drugs, two important steps required in the production of bacterial proteins are interrupted, and the combination is more effective than either drug alone. Bactrim was approved by the FDA in 1973.

PRESCRIPTION: Yes

GENERIC AVAILABLE: Yes

�PREPARATIONS: Tablets: 160 mg trimethoprim and 800 mg sulfamethoxazole (Bactrim DS, Septra DS); 80 mg trimethoprim and 400 mg sulfamethoxazole (Bactrim; Septra).

STORAGE: The tablets should be kept at room temperature, 15-30 C (59-86 F).

PRESCRIBED FOR: Sulfamethoxazole/trimethoprim is used for treating infections due to susceptible bacteria. Examples include urinary tract infections, flares of chromic bronchitis due to bacteria, middle ear infections, for prevention of infections due to pneumococcus in organ transplant recipients, for the treatment or prevention of Pneumocystis carinii pneumonia, chancroid, and prevention of toxoplasma encephalitis in patients with AIDS.

DOSING: The recommended adult dose for urinary tract infections is one double strength tablet (Bactrim DS, Septra DS) or two single strength tablets every 12 hours for 10 to 14 days.

Flares of chronic bronchitis are treated with a similar regimen for 14 days.

Sulfamethoxazole/trimethoprim should be taken with 6 to 8 ounces of liquid to prevent crystals from forming in the urine. Persons with advanced kidney disease may require lower doses.

DRUG INTERACTIONS: Sulfamethoxazole/trimethoprim 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 acidic urine, it should not be used with sulfonamides.

Blood levels of phenytoin (Dilantin) may be increased by treatment with sulfamethoxazole/trimethoprim. This may lead to side effects associated with phenytoin (Dilantin, Dilantin-125) such as dizziness, and reduced attention. S

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Suggested Reading on sulfamethoxazole and trimethoprim, Bactrim, Septra by Our Doctors

- Urinary Tract Infection (UTI In Adults)
  - Urinary tract infection (UTI) is an infection of the kidney, ureter, bladder, and/or urethra. Not everyone with a UTI has symptoms. Common symptoms include a frequent urge to urinate and a painful, burning when urinating.
- Kidney Infection
  - Kidney infection (pyelonephritis) usually is caused from bacteria that have spread from the bladder from a UTI (urinary tract infection), poor hygiene, sexual intercourse, pregnancy, catheter, cystoscope exam, surgery, kidney stones, or prostate enlargement. Symptoms of kidney infection include: back pain, frequent urination, pain during urination, fever, and or pus or blood in the urine. Kidney infection is usually treated with antibiotics.
- MRSA
  - MRSA (methicillin resistant Staphylococcus aureus) bacteria causes skin infections with the following signs and symptoms: cellulitis, abscesses, carbuncles, impetigo, styes, and boils. Normal skin tissue doesn't usually allow MRSA infection to develop. Individuals with depressed immune systems and people with cuts, abrasions, or chronic skin disease are more susceptible to MRSA infection.
- Human Immunodeficiency Virus
  - HIV (human immunodeficiency virus) is the cause of AIDS (acquired immunodeficiency syndrome). HIV is a type of virus called a retrovirus, which infects humans when it comes in contact with a break in the skin or tissues such as those that line the vagina, anal area, mouth, or eyes.
- Impetigo
  - Impetigo is a contagious skin infection caused by staph and strep bacteria. There are two types of impetigo: non-bullous and bullous. Symptoms of non-bullous impetigo include small blisters on the nose, face, arms, or legs and possibly swollen glands. Bullous impetigo symptoms include blisters in various areas, particularly in the buttocks area. Treatment involves gentle cleansing, removing the crusts of popped blisters, and the application of prescription-strength mupirocin antibiotic ointment.
- Whooping Cough (Pertussis)
  - Whooping 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). Whopping 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.
- Ear Infection (Otitis Media)
  - Middle ear infection or inflammation (otitis media) is inflammation fo the middle ear. There are two types of otitis media, acute and chronic. Acute otitis media is generally short in duration, and chronic otitis media generally lasts several weeks. Seventy-five percent of children in the U.S. suffer from otitis media at some point. Treatment depends upon the type (chronic or acute).
- Listeria
  - Listeria is a type of bacteria that can cause food poisoning. Listeriosis symptoms include diarrhea, nausea and fever. Pregnant women are 20 times more likely than other healthy adults to get listeriosis. Listeria infection is treated with antibiotics.
- Toxoplasmosis
  - Toxoplasmosis (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.
- Wegener's Granulomatosis
  - Wegener's granulomatosis, a condition that usually affects young or middle-aged adults, is an inflammation of the arteries supplying blood to the sinuses, lungs, and kidneys. Symptoms of Wegener's granulomatosis include bloody sputum, fatigue, weight loss, joint pain, sinusitis, shortness of breath, and fever. Wegener's granulomatosis may be fatal within months without treatment. Treatment aims to stop inflammation with high doses of prednisone and cyclophosphamide.
- Brucellosis
  - Brucellosis is an infectious disease caused by the Brucella bacteria. Symptoms and signs include sweating, fever, fatigue, dizziness, headache, cough, chest, joint, and abdominal pain, and enlarged liver and/or spleen. Brucellosis is treated with antibiotics.
- Shigella
  - Shigellosis is a disease caused by the Shigella bacteria. Bloody diarrhea, stomach cramps and fever are common symptoms. Mild infections usually resolve on their own. Antibiotics are used to treat more severe cases.
- Mycobacterium Marinum
  - Mycobacterium marinum (M. marinum) is bacteria found in fresh and saltwater that can infect the skin through cuts or scrapes, causing granulomas to appear on the skin near the site of infection. This infection may be treated with a long course of oral antibiotics.
- Enterovirulent E. Coli (EEC)
  - Enterovirulent Escherichia coli (E. coli) are strains of related bacteria that have a strong propensity to cause gastrointestinal tract infections. Examples of strains include: EHEC (enterohemorrhagic E. coli), ETEC (enterotoxigenic E. coli), EPEC (enteropathogenic E. coli), EIEC (enteroinvasive E. coli), EAEC (enteroadherent E. coli), and EAggEC (enteroaggregative E. coli). Symptoms may vary depending on the strain the individual contracts. Infection is spread generally through contaminated food or drink.

Symptom Checker: Your Guide to Symptoms & Signs: Pinpoint Your Pain

sulfamethoxazole and trimethoprim, Bactrim, Septra

Kidney Infection �

What is the function of the kidneys?

The kidneys have a variety of important functions in the body. These include filtering the waste products from the blood as it circulates through capillaries within the kidneys, regulating blood pressure, maintaining steady levels of electrolytes (for example, calcium, phosphorus, sodium, potassium, and chloride), and contributing to the production of red blood cells.

Where are the kidneys located?

The kidneys are located on either side of the body underneath the diaphragm near the lower back. Each kidney is connected to the bladder in the pelvis by ureters (long tube-like structures) that drain the urine from the kidneys to the bladder. Urine stored in the bladder is excreted from the body through the urethra.