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Keflex vs Ceclor

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Keflex Information

Ceclor Information

Comparative Analysis

Keflex Prescription Information

Ceclor Prescription Information

Keflex Side Effects

Ceclor Side Effects

Safety Information

Cost Information

Market Information



For patients with bacterial infections, certain antibiotics that target the growth and proliferation of bacteria can help in managing symptoms and speeding up recovery. Keflex (Cephalexin) and Ceclor (Cefaclor) are two such drugs that are prescribed for this purpose. Both fall under the category of cephalosporins but they belong to different generations with Keflex being a first-generation cephalosporin while Ceclor is classified as second generation. They each impact different types of bacteria but both have bactericidal effects, meaning they kill bacteria directly. Keflex works by inhibiting bacterial cell wall synthesis leading to cell death especially on gram-positive cocci whereas, Ceclor has similar action but it is more effective against Haemophilus influenzae compared to first-generation agents like Keflex.

Keflex vs Ceclor Side By Side

Brand NameKeflexCeclor
ContraindicationsAllergy to cephalosporins or penicillins, interaction with live bacterial vaccines and probenecid.Allergy to cephalosporins or penicillins, interaction with certain medications that may lead to severe reactions.
CostFor brand name: around $300 for 28 capsules of 500 mg. For generic (cephalexin): starts from $0.50 to $1 per capsule.For brand name: around $540 for a similar quantity and dose. For generic (cefaclor): starts as low as around one dollar per capsule.
Generic NameCephalexinCefaclor
Most Serious Side EffectSigns of an allergic reaction, severe stomach/abdominal pain, persistent nausea/vomiting, Clostridium difficile-associated diarrhea.Allergic reactions, severe skin reactions, watery or bloody diarrhea, jaundice, unusual changes in mood or behavior, kidney problems, liver issues.
Severe Drug InteractionsLive bacterial vaccines, probenecid.Specific interactions not detailed, but caution advised with any medication that could interact negatively.
Typical Dose250-1000 mg every 6 hours; up to 4000 mg/day.250–500 mg every 8 hours; up to 4 grams per day.

What is Keflex?

Cephalexin (the generic name for Keflex) was one of the first drugs in a class of antibiotics known as cephalosporins. It was approved by the FDA in 1971. Keflex works to fight off bacterial infections by acting on their cell wall, thus inhibiting its formation and eventually leading to bacterial death. It's commonly prescribed for various types of bacterial infections including those affecting skin, ear, respiratory tract among others.

On the other hand, Ceclor falls under another type of cephalosporin antibiotic called "second generation", characterized by its broader spectrum against Gram-negative bacteria compared to first-generation cephalosporins like Keflex. The active ingredient is Cefaclor which also destructs bacterial cell walls leading to their demise but has an expanded coverage than Cephalexin.

Both these medications have been noted for their relative safety profiles with most side effects being mild such as gastrointestinal disturbances although some individuals might be allergic especially if there’s a history of penicillin allergy.

What conditions is Keflex approved to treat?

Keflex and Ceclor are both approved for the treatment of a variety of bacterial infections:

  • Keflex (cephalexin) is often used in treating skin infections, bone infections, ear infections, urinary tract infections (UTIs), and respiratory tract infections.
  • Ceclor (cefaclor) is similarly utilized to treat various types of bacterial conditions such as pneumonia; ear, lung, throat, urinary tract and skin infection.

How does Keflex help with these illnesses?

Keflex is an antibiotic that works by inhibiting the synthesis of bacterial cell walls. It accomplishes this by binding to specific proteins, known as penicillin-binding proteins, which are needed to construct these important structures. As bacteria cannot survive without a functional cell wall, Keflex effectively kills them and helps control infection.

Ceclor, on the other hand, also belongs to the class of antibiotics known as cephalosporins. Like Keflex, it fights bacterial infections by disrupting their ability to build their protective cell walls. However, Ceclor is part of a different generation within this group of medications and may offer broader coverage against certain types of bacteria compared with Keflex.

Both antibiotics can be highly effective in treating various types of bacterial infections including skin infections or respiratory tract infections but choosing between them often depends upon factors like patient allergy history or type and location of infection.

What is Ceclor?

Ceclor, also known as cefaclor, is a second-generation cephalosporin antibiotic. It works by inhibiting the synthesis of bacterial cell walls, leading to cell death and effectively combating a variety of infections. Ceclor was first approved by the FDA in 1979 and has been widely used since then for treating respiratory tract infections, skin and soft tissue infections among others. Unlike Keflex (also an antibiotic but from the first-generation cephalosporins), Ceclor is more resistant to beta-lactamase enzymes produced by some bacteria which can degrade antibiotics rendering them ineffective. This means that it can be effective against certain types of bacteria where Keflex might not be. Moreover, its side-effect profile differs from that of Keflex; while both drugs could potentially cause allergic reactions or gastrointestinal discomforts like diarrhea or nausea, pseudomembranous colitis (a severe form of diarrhea) seems less common with Ceclor compared to other antibiotics such as Keflex.

What conditions is Ceclor approved to treat?

Ceclor is a highly effective antibiotic that is approved for treating various bacterial infections. Its spectrum of activity includes:

  • Streptococcal pharyngitis (Strep throat)
  • Otitis media (middle ear infection)
  • Sinusitis
  • Lower respiratory tract infections such as pneumonia or bronchitis
  • Skin and skin structure infections caused by susceptible bacteria

How does Ceclor help with these illnesses?

Ceclor, also known as cefaclor, is a second-generation cephalosporin antibiotic. It works by inhibiting the synthesis of bacterial cell walls which ultimately leads to their death. This drug plays critical roles in treating various infections caused by susceptible organisms like Streptococcus pneumoniae and Staphylococcus aureus. Ceclor's action against both gram-positive and gram-negative bacteria makes it a broad spectrum antibiotic, a valuable tool for physicians when dealing with undiagnosed bacterial infections. Unlike Keflex (cephalexin), which belongs to the first generation of cephalosporins and primarily targets gram-positive bacteria only, Ceclor has enhanced activity against certain types of gram-negative bacteria such as Haemophilus influenzae and Moraxella catarrhalis. Therefore, doctors may prescribe Ceclor over Keflex when they suspect an infection might be caused by these specific types of bacteria.

How effective are both Keflex and Ceclor?

Both cephalexin (Keflex) and cefaclor (Ceclor) are effective antibiotics, falling under the broad category of cephalosporins. They were approved by the FDA in 1971 and 1978 respectively. Since they act on different generations of cephalosporins, they may be prescribed for slightly different bacterial infections. The effectiveness of Keflex and Ceclor was directly studied in a double-blind clinical trial in 1987; both drugs exhibited similar efficacy in managing symptoms of urinary tract infections as well as comparable safety profiles.

A review conducted in 2002 illustrated that Keflex is rapidly absorbed after oral administration, reaches peak plasma concentrations about one hour post-dose, and has an elimination half-life averaging around two hours. It's often used to treat skin infections, upper respiratory infections, otitis media, urinary tract infections among others due to its ability to fight against a wide spectrum of bacteria including Staphylococcus aureus which is an important cause for these conditions.

On the other hand, a study done back in 1995 showed that Ceclor was more effective than placebo at treating acute otitis media with effusion (fluid buildup) which can lead to hearing loss if untreated. Though it belongs to second-generation cephalosporins which generally have broader spectrum activity compared to first generation like Keflex,it is less likely than third- or fourth-generation agents like ceftazidime or cefepime respectively,to cross the blood-brain barrier so it's not typically chosen for central nervous system infection treatments unless others are contraindicated.

It’s essential when choosing between these two antibiotics that individual patient factors are taken into account such as renal function because dose adjustment might be necessary depending on how severe their kidney disease is since both drugs predominantly excreted unchanged through kidneys.Also allergies should be considered because though rare some people could exhibit hypersensitivity reaction towards certain components present within these medications.

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At what dose is Keflex typically prescribed?

Oral dosages of Keflex range from 250-1000 mg every 6 hours, but studies have indicated that a dosage of 500 mg every 12 hours is sufficient for treating many common bacterial infections in most people. Children may be started on a dose calculated based on their body weight, typically at a rate of 25 to 50 mg/kg per day divided into equal doses throughout the day. In either population, the dosage can be increased after a few days if there is no response. The maximum dosage that should not be exceeded in any case is 4000 mg/day.

At what dose is Ceclor typically prescribed?

Ceclor treatment typically commences with a dosage of 250–500 mg every 8 hours. The dose can then potentially be increased to a maximum of 4 grams per day, divided into equal doses spaced around the clock, if there's no response or improvement after initial administration. For more severe infections, such as pneumonia and endocarditis, the Ceclor dosage may be doubled. As always, duration and dosages should strictly adhere to your doctor's instructions based on health conditions and individual responses to the medication.

What are the most common side effects for Keflex?

Common side effects associated with Keflex and Ceclor include:

  • Diarrhea
  • Nausea or vomiting
  • Dyspepsia (stomach discomfort, indigestion)
  • Dizziness
  • Fatigue (general weakness and tiredness)
  • Headache
  • Rash, hives, or itching
  • Abnormal liver function tests
  • Joint pain
  • Vaginal itching or discharge

It's important to note that while these side effects are common, they do not occur in everyone. If you experience any of these symptoms persistently or severely whilst using either Keflex or Ceclor, consult your healthcare provider.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Keflex?

When comparing Keflex and Ceclor, two commonly prescribed antibiotics, it's important to be aware of the potential side effects:

  • Signs of an allergic reaction: hives; difficulty breathing; swelling in your face or throat. If you experience these symptoms after taking either medication, seek immediate medical attention.
  • Symptoms related to liver problems: yellowing eyes/skin (jaundice), severe stomach/abdominal pain, persistent nausea/vomiting
  • Severe dizziness or fainting spells may occur due to a rapid drop in blood pressure; if this happens, stop what you're doing and sit down until it passes.
  • If you have kidney disease or dysfunction while on these medications watch out for changes in amount of urine passed.
  • In rare cases there could be a serious intestinal condition due to resistant bacteria(Clostridium difficile). This can occur during treatment or weeks after treatment has stopped. Do not use anti-diarrhea products if such symptoms develop as they make them worse.

While both drugs are generally well-tolerated by most patients and effective at combating bacterial infections when used appropriately, it's crucial that you tell your healthcare provider about any allergies before starting these medications because both contain cephalosporin which might trigger serious allergic reactions in those sensitive to this class of drug.

What are the most common side effects for Ceclor?

Potential side effects of Ceclor include:

  • Upset stomach or vomiting
  • Diarrhea, which may be severe
  • Skin rash and itching
  • Headache or dizziness
  • Joint pain
  • Fatigue or general malaise
  • Changes in urination patterns While Ceclor does not typically cause dry mouth, a sore throat or stuffy nose, if you notice these symptoms it might indicate an allergic reaction. Furthermore, unlike Keflex, Ceclor can sometimes lead to confusion or agitation; however this is less common. It's important to share with your healthcare provider all the medications you're currently taking for a comprehensive understanding of potential interactions and side effects.

Are there any potential serious side effects for Ceclor?

Ceclor, while generally well-tolerated, can present some severe side effects in rare instances. It's important to be aware of these possible reactions:

  • Indications of an allergic reaction such as hives; difficulty breathing; swelling in your face, lips, tongue or throat
  • Severe skin reactions like fever, sore throat, swelling in your face or tongue, burning eyes and a red or purple skin rash that spreads with blistering and peeling
  • Diarrhea that is watery or bloody
  • Jaundice (yellowing of the skin or eyes)
  • Unusual changes in mood or behavior
  • Signs pointing towards kidney problems: little to no urination; painful urination; fluid retention causing swelling in your feet or ankles; feeling tired
  • Liver issues symptoms: nausea, upper stomach pain, itching

Should you experience any of these effects after taking Ceclor stop taking the medication immediately and consult with a medical professional right away.

Contraindications for Keflex and Ceclor?

Both Keflex and Ceclor, like many other antibiotics, may cause adverse reactions in some individuals. If you notice any signs of allergic reactions such as hives; difficulty breathing or swallowing; swelling of your lips, face, tongue or throat: seek immediate medical attention.

Neither Keflex nor Ceclor should be taken if you are allergic to cephalosporins or penicillins. An allergy to either class of medication could lead to a severe and potentially life-threatening allergic reaction when taking Keflex or Ceclor. Always inform your physician about any known allergies and previous reactions to medications.

Furthermore, these antibiotics can interact negatively with certain other medicines including live bacterial vaccines (like typhoid vaccine) and probenecid among others. Therefore, it's essential that you tell your healthcare provider about all the medications and supplements you're currently taking.

Both drugs may also increase the risk of overgrowth of bacteria not affected by the antibiotic which can lead to secondary infection - an indication for this is new infections during treatment such as oral thrush or yeast infections.

Lastly, prolonged use of these antibiotics without a doctor's supervision could decrease their effectiveness over time due to bacteria developing resistance against them.

How much do Keflex and Ceclor cost?

For the brand name versions of these drugs:

  • The price of 28 capsules of Keflex (500 mg) averages around $300, which works out to about $10.70 per day.
  • The price for a similar quantity and dose of Ceclor is significantly higher, averaging at about $540 or close to $19.30/day.

Thus, if you are in the higher dosage range for Keflex (i.e., 2000 mg/day), then brand-name Ceclor becomes more expensive on a per-day treatment basis. Please note that cost should not be a primary consideration in determining which drug is right for you.

For generic versions of Keflex (cephalexin) and Ceclor (cefaclor), costs are considerably lower:

  • Cephalexin (500 mg tablets) can be obtained in packs starting from 20 capsules with approximate prices ranging from $0.50 to $1 per capsule depending on your location and insurance status.
  • On the other hand, cefaclor is available in packages starting from 15 up to several hundred capsules (250 mg each). The cost starts as low as around one dollar per capsule but does depend heavily on factors like where you live and your insurance coverage parameters.

As always when choosing medication: consider effectiveness, side effects, interactions with other substances you may take regularly - not just cost considerations alone!

Popularity of Keflex and Ceclor

Cephalexin, also known by its brand name Keflex, was prescribed to around 5.2 million people in the United States in 2019. It belongs to the first-generation cephalosporins and accounts for a substantial portion of prescriptions within this class of antibiotics due to its broad-spectrum activity against both Gram-positive and some Gram-negative bacteria.

On the other hand, Cefaclor, commonly recognized by its brand name Ceclor, is not as frequently prescribed. As a second-generation cephalosporin, it has a broader range of action against more types of bacteria compared to cephalexin but was only prescribed approximately half-a-million times in 2019.

Over time there hasn't been any significant change regarding their prescription rates; however, with increasing bacterial resistance patterns worldwide these statistics might see changes over future years.


Both Keflex (cephalexin) and Ceclor (cefaclor) have a long-standing record of usage in treating bacterial infections, with numerous clinical studies showing their effectiveness against a variety of pathogens. They belong to the same class of antibiotics known as cephalosporins but differ slightly in terms of their generation - Keflex is a first-generation drug while Ceclor belongs to the second generation. This difference affects their spectrum of activity, with Ceclor generally having broader coverage than Keflex.

Keflex tends to be prescribed for skin and soft tissue infections as well as urinary tract infections due its excellent Staphylococcus aureus and E.coli coverage. On the other hand, Ceclor is used more often when targeting respiratory tract pathogens such as Haemophilus influenzae or Moraxella catarrhalis because it has better coverage against these bacteria.

Both drugs are available in generic forms which can help patients save costs. The onset of effect for both medications should be within 1-2 days after starting treatment if no resistance exists.

The side effects between these two drugs are similar; potential issues include gastrointestinal discomforts like nausea, vomiting or diarrhea. However, allergy concerns exist especially among people who show hypersensitivity reactions towards penicillin since cross-reactivity may occur within cephalosporins like Keflex and Ceclor. Therefore, close monitoring during initial stages of therapy is crucial and any signs suggestive of an allergic reaction warrants immediate medical attention.