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Keflex (cephalexin) is one of several medications used to treat urinary tract infections (UTIs). Whether it’s the right drug for you depends on things like other medications you’re taking and any additional medical conditions you may have.
If you’ve been diagnosed with a urinary tract infection (UTI), your doctor may have prescribed an antibiotic called Keflex. An antibiotic is a medication used to treat infections caused by bacteria.
Keflex is more often prescribed in its generic version, called cephalexin. This article can help you understand more about UTIs and what you can expect from treatment with Keflex or cephalexin.
If your doctor prescribes Keflex to treat your UTI, you’ll likely take the drug at home. Treatment typically lasts no longer than 7 days. Antibiotic resistance is a growing problem which is why it’s recommended to take the shortest course of antibiotics that’s effective for your condition.
As with all antibiotics, you should take Keflex exactly as your doctor prescribes. Take the entire course of treatment even if you start to feel better.
Never stop treatment early. If you do, the infection could return and get worse. Also, be sure to drink plenty of fluids during your treatment.
Keflex is a brand name drug that’s also available as the generic drug cephalexin. Keflex belongs to a class of drugs called cephalosporins, which are antibiotics. These drugs are often used to treat infections of the bladder or kidneys.
Keflex is used in adults to treat several types of bacterial infections, including UTIs. It’s available as a capsule you take by mouth. It works by stopping bacterial cells from forming properly.
Common side effects
The more common side effects of Keflex can include:
- upset stomach
- nausea and vomiting
Serious side effects
In some cases, Keflex can cause serious side effects. These can include:
Serious allergic reaction
Symptoms can include:
- hives or rash
- trouble breathing or swallowing
- swelling of your lips, tongue, or face
- throat tightness
- a rapid heart rate
Symptoms can include:
- pain or tenderness in your abdomen
- dark urine
- yellowing of your skin or the whites of your eyes
Keflex will kill only certain types of bacteria, so other types may continue to grow and cause other infections. Your doctor can tell you more. Symptoms of infections can include:
- body aches
An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well. Before starting Keflex, tell your doctor about all medications, vitamins, or herbs you’re taking. This can help your doctor prevent possible interactions.
Examples of drugs that can interact with Keflex include probenecid and birth control pills.
Other health conditions of concern
Keflex may not be a good choice if you have certain health conditions. Be sure to discuss your health history with your doctor before they prescribe Keflex or any other drug to treat your UTI.
Examples of conditions that could cause problems with Keflex include kidney disease and allergies to penicillin or other cephalosporins.
Pregnancy and breastfeeding
Keflex is typically considered safe during pregnancy. It hasn’t been shown to cause birth defects or other problems for pregnant women and their babies.
Keflex can pass to a child through breast milk. If you breastfeed your child, talk with your doctor about whether you should stop breastfeeding or if you should take a different drug for your UTI.
Urinary tract infections (UTIs) are typically caused by bacteria. These infections can occur anywhere in your urinary tract, including your kidneys, bladder, or urethra. (Your urethra is the tube that carries urine from your bladder out of your body.)
The bacteria that cause a UTI can come from your skin or your rectum. These germs travel into your body through your urethra. If they move into your bladder, the infection is called bacterial cystitis.
In some cases, the bacteria move from the bladder into the kidneys. This causes a much more serious condition called pyelonephritis, which is inflammation of the kidneys and surrounding tissue.
Women are more likely than men to get UTIs. This is because a woman’s urethra is shorter than a man’s, which makes it easier for bacteria to reach the bladder.
The more common symptoms of a UTI can include:
- pain or burning during urination
- frequent urination
- feeling an urge to urinate even if your bladder is empty
- cloudy or bloody urine
- pressure or cramping in your lower abdomen
Symptoms of pyelonephritis include:
- frequent, painful urination
- pain in your lower back or side
- a fever greater than 101°F (38.3°C)
- nausea or vomiting
- delirium (severe confusion)
If you notice any symptoms of a UTI, call your doctor. Call them right away if you have symptoms of pyelonephritis.
Your doctor will likely order a urine test to confirm that you have a UTI before treating you. This is because UTI symptoms can be similar to symptoms caused by other problems. If the test results show that you have a UTI, your doctor will likely prescribe an antibiotic such as Keflex.
Keflex is one of several antibiotics that can be used to treat UTIs. Your doctor will choose the best one for you based on your health history, other drugs you’re taking, and other factors.
If your doctor prescribes Keflex, they can tell you more about this drug. Discuss this article with your doctor and ask any questions you may have. The more you know about your treatment options, the more comfortable you’ll likely feel with your care.
Your doctor may also prescribe other medications for treatment that are not antibiotic based.