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Keflex (Cephalexin)

Keflex (Cephalexin)

Keflex comes in an oral capsule and is a prescription drug that will only be available after a discussion with your doctor. Generic versions of this medication are also available. More information

A doctor will review your order and write you a prescription, if appropriate. This prescription is then forwarded to a pharmacy. The pharmacy will have your medicine delivered to you within one to three working days. Read more about this process here.

Keflex is the brand name for a medication with the active ingredient "cephalexin". It's an antibiotic that works by fighting the bacteria in your body. This substance can be used to treat a range of infections caused by a build up of bacteria, including ear infections, respiratory infections, skin infections, ear infections, and more. This substance may also be used for other purposes.  

What is Keflex? 

Keflex comes in an oral capsule and is a prescription drug that will only be available after a discussion with your doctor. Generic versions of this medication are also available. Keflex is an oral tablet or oral suspension substance that belongs to the antibiotic class of drugs. This medication works by interfering with the formation of the bacteria's cell walls, which ruptures the form of the bacteria and kills the infection.  

This drug is intended only for the treatment of bacterial infections and cannot be used to treat viral infections. Your doctor will determine whether Keflex is the right treatment for you based on your symptoms, medical background and condition.  

When is Keflex used? 

The Keflex antibiotic belongs to the cephalosporin family, making it excellent for the treatment of infections that are caused by a build-up of bacteria. Usually, this medication is used to treat the respiratory tract, as well as skin, bone, and middle ear infections. It can occasionally be used for the treatment of urinary tract infections. Keflex is also used to prevent infections that are caused by exposure to bacteria in the streptococcal family and may be caused to reduce your risk of rheumatic fever. In some medical circles, this medication is referred to as a first generation antibiotic, because it was one of the initial medications to be discovered and marketed.  

Cephalexin, an antibiotic in the cephalosporin family, is used to treat  

How do you use Keflex? 

Keflex is taken by mouth, often with a drink of water, according to the instructions given by your doctor. Usually, you will be required to take this medication once every 6 to 12 hours with or without food. Some people find that it is better to take an antibiotic with food, because it reduces their risk of stomach upset. However, it's not necessary to eat before taking this drug.  If you are using the liquid suspension version of Keflex, then you will need to shake the bottle before you take a dose. Make sure that you measure your medication carefully using a special spoon or measuring device. The dosage you are given will depend on your response to treatment and condition. In children, dosage will be based on the weight of the child.  

To make sure that you get the best response from this medication, make sure that you take your antibiotic at evenly spaced times, usually at the same time each day. You will need to continue taking this medication until the full amount is finished. Do not stop taking the drug ahead of time, even if you start to feel better or your symptoms disappear.  

What dosages are available? 

The dose of Keflex that is given to you by your doctor will depend on the nature of your infection and your medical background. The usual dose for an adult can range between 1 and 4 grams of the antibiotic per day, given in divided doses. You may also take 250mg every 6 hours, or 500mg every 12 hours.  

The tablet version of Keflex is available in 250mg, 333mg, 500mg, and 750mg options.  

What are the side effects of Keflex? 

Keflex like other medications may cause unwanted side effects with some people. Certain patients will not have any response to this drug. Remember to tell your doctor about any unusual responses you have to your medications, even if they are not listed as a side effect.  

The most common side effects of Keflex include indigestion, diarrhea, irritation, inflammation of the stomach lining and stomach pain. If these effects are relatively mild, then they may go away within a few days. If the conditions persist or worsen, speak to your pharmacist or doctor. Call your doctor immediately if you experience any more serious side effects such as trouble breathing, swelling of the tongue, lips or throat, or hives.  This medication may cause an intestinal condition due to the presence of highly resistant bacteria. Don't use any anti-diarrhea treatments if you have blood in your stool, abdominal pain, or persistent diarrhea, because your conditions could be made worse. You will need to contact your doctor immediately if severe gastrointestinal side effects occur, as this could be a sign that you're suffering from negative reactions caused by the bacteria in your body.  

When shouldn't you use Keflex? 

There are people who will not be suitable for treatment with Keflex. If you are allergic to penicillin, for instance, then there's a chance that you could also be allergic to the active ingredients in this medication. You also may have a higher risk of side effects when taking Keflex if you have a history of colon disease, kidney or liver issues, and other problems with the organs in your stomach or abdomen.  

If you have a history of kidney problems, then you will not be able to clear this drug from your body properly, which could lead to an increased level of this substance in your blood. This may also increase the chance that you experience side effects. Talk to your doctor about your condition and you may be able to take an adjusted dose of Keflex.  Similarly to other antibiotics, Keflex can sometimes lead to an overgrowth of bacteria in the colon. Being on other antibiotics may also increase your risk of this condition, so talk to your doctor about recent antibiotic use.  

For pregnant women, Keflex might not suitable, but there are no studies to suggest that the drug poses a risk to your fetus. It's best to speak to your doctor about the benefits and risks. Additionally, remember that Keflex passes into breast milk, and causes side effects in children who are breastfed. Talk to your doctor if you are breastfeeding your child.  

For seniors, it's important to be cautious when taking Keflex. This substance can be dangerous to take for people with kidney conditions, and older people may find that their kidneys don't work as well as the kidneys in younger people. If you are above a certain age, your doctor will probably prescribe you a lower dose of Keflex because it is more likely to remain within your body for a longer period of time. Additionally, your risk of side effects may be higher with Keflex if you are above a certain age, because the drug can build up in the blood stream.  

Does Keflex interact with any other medications? 

It is possible that Keflex could interact with other drugs that you are already taking. Before taking any new medication, make sure that you speak to your doctor about any of the over the counter medications that you are using or have used recently, as well as prescription drugs that you take on a regular basis. Various vitamins, dietary supplements and herbal medications are also important to mention, as these substances can also interact with Keflex.  There are some drugs that are already known to interact with this medication. For instance, Keflex can increase the blood levels of a type 2 drug used for the treatment of diabetes, called metformin. This increases your chances of suffering from side effects. Additionally, Keflex can begin to build to dangerous levels in the blood when combined with the medication that is used for the treatment of gout, probenecid.  

Keflex may sometimes be used alongside other antibiotics to increase the strength of the treatment. However, this drug will not work well with all antibiotics. Take your doctor's advice when using multiple treatments. Using antibiotics can make certain birth control pills ineffective too. Speak to your doctor about whether this substance will harm your contraceptive pill usage, and make sure you use a secondary form of contraception.  

Where can you buy Keflex? 

Keflex is available in both tablet and liquid suspension form from registered pharmacies both online and offline. These substances are not approved to be taken without a prescription, which means that you will need to have a medical assessment done by a doctor before you can begin taking this substance. Do not buy Keflex from any company that claims they can offer you it without a prescription.  

Can you get Keflex without a prescription?  

In the UK Keflex is not available to obtain without a prescription. You will need to speak to your doctor about your complete medical history and situation so that you can ensure you are getting the right treatment. If Keflex is not appropriate for you, then your doctor might suggest another form of antibiotic.  




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Assessed by:

Dr Imran Malik, General practitioner
Registration number: GMC: 4741365

Dr Imran Malik studied undergraduate medicine at King's College University in Central London and clinical studies at the prestigious King's College Hospital. He graduated with a MBBS degree in 2000 and went on to gain postgraduate memberships with the Royal Society of Medicine and also General Practice in 2006.