Omnicef vs Keflex

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Table of Contents

Overview

Omnicef Information

Keflex Information

Comparative Analysis

Omnicef Prescription Information

Keflex Prescription Information

Omnicef Side Effects

Keflex Side Effects

Safety Information

Cost Information

Market Information

Summary

Overview

Omnicef Information

Keflex Information

Comparative Analysis

Omnicef Prescription Information

Keflex Prescription Information

Omnicef Side Effects

Keflex Side Effects

Safety Information

Cost Information

Market Information

Summary

Introduction

For patients dealing with bacterial infections, certain antibiotics that inhibit the growth of or kill bacteria can help in managing symptoms and resolving the infection. Omnicef (cefdinir) and Keflex (cephalexin) are two such drugs that are frequently prescribed for treating a variety of bacterial infections. They each belong to separate generations within the cephalosporins class of antibiotics, but both have bactericidal effects in fighting against susceptible bacteria. Omnicef is a third-generation cephalosporin known for its broad-spectrum activity against Gram-negative bacteria along with some Gram-positive pathogens. On the other hand, Keflex is described as a first-generation cephalosporin primarily effective against Gram-positive cocci and selected Gram-negative bacilli.

Omnicef vs Keflex Side By Side

Attribute	Omnicef	Keflex
Brand Name	Omnicef	Keflex
Contraindications	Allergic reaction to cephalosporin antibiotics, caution needed for those allergic to penicillin-type drugs due to possible cross-reactivity	Allergic reaction to cephalosporin antibiotics, caution needed for those allergic to penicillin-type drugs due to possible cross-reactivity
Cost	Approximately $15 - $45 for a generic 5-10 day treatment plan	Approximately under $1 up to around $2 per day for a generic version
Generic Name	Cefdinir	Cephalexin
Most Serious Side Effect	Severe skin reaction, Clostridium difficile-associated diarrhea	Signs of an allergic reaction or severe skin reaction, confusion, agitation, hallucinations
Severe Drug Interactions	Not specifically mentioned in the text	Not specifically mentioned in the text
Typical Dose	300–600 mg/day, divided into one or two doses	250-500 mg every 6 hours or 500 mg every 12 hours, up to 4000 mg/day

What is Omnicef?

Cefdinir (the generic name for Omnicef) and Cephalexin (the generic name for Keflex) are both cephalosporin antibiotics that were developed to combat bacterial infections. These drugs inhibit the formation of bacterial cell walls, effectively killing them off. Cefdinir was first approved by the FDA in 1997, marking its place as a later generation antibiotic with broader spectrum activity against a wide range of bacteria compared to earlier generations. It is primarily prescribed for treating various forms of skin infections, respiratory tract infections like pneumonia and sinusitis among other conditions. On the other hand, Cephalexin which belongs to an earlier generation has been around much longer since it was approved by the FDA in 1971 but is no less effective when used appropriately particularly against Gram-positive bacteria such as Staphylococcus and Streptococcus species . Both medications have similar side effect profiles including diarrhea, nausea or vomiting but these tend to be mild and manageable.

What conditions is Omnicef approved to treat?

Omnicef is approved for the treatment of a variety of bacterial infections including:

Community-acquired pneumonia
Acute exacerbation of chronic bronchitis
Acute maxillary sinusitis
Pharyngitis/tonsillitis
Uncomplicated skin and skin structure infections Keflex, on the other hand, is used to treat different types of bacterial infections such as:
Respiratory tract infection
Otitis media (ear infection)
Skin and soft tissue infection
Bone infections.

How does Omnicef help with these illnesses?

Omnicef, also known as cefdinir, is a third-generation cephalosporin antibiotic that combats bacteria by inhibiting the synthesis of peptidoglycan, an important component in bacterial cell walls. Without this essential structure, the bacterial cells become vulnerable and ultimately die off. This makes Omnicef effective against a broad range of gram-positive and gram-negative bacteria.

Keflex or cephalexin is a first-generation cephalosporin with a similar mechanism of action to Omnicef; it disrupts the production of peptidoglycan layers within bacterial cell walls leading to cellular death. However, Keflex primarily targets gram-positive bacteria rather than having a more extensive reach like Omnicef.

Both antibiotics are used for treating various types of infections but their application could depend on the specific strain causing an infection. Therefore, understanding these differences can help patients better manage their condition under doctor's supervision.

What is Keflex?

Keflex is a brand name for cephalexin, which is a first-generation cephalosporin antibiotic. It acts by inhibiting the synthesis of bacterial cell walls, leading to cell death. It was first approved by the FDA in 1971 and has been widely used since then due to its broad-spectrum activity against both gram-positive and some gram-negative bacteria.

Cephalexin does not affect human cells as they do not have cell walls, this makes it selectively toxic to bacteria only. This specificity means that side-effects are typically mild and include gastrointestinal upset such as diarrhea or nausea. Keflex can also cause allergic reactions in those with sensitivities or allergies to penicillin antibiotics.

The use of cephalexin can be beneficial for treating common bacterial infections such as strep throat, ear infections, skin infections among others - especially in patients who do not respond well or are resistant to other types of antibiotics.

What conditions is Keflex approved to treat?

Keflex is an antibiotic that has been approved for the treatment of:

Respiratory tract infections, such as pneumonia and bronchitis
Ear infections (otitis media)
Skin and soft tissue infections
Bone infections (osteomyelitis)
Urinary tract infections

This makes Keflex a versatile tool in the fight against bacterial illnesses.

How does Keflex help with these illnesses?

Keflex, generically known as cephalexin, is an antibiotic that fights bacteria in the body by interrupting their cell wall synthesis. It belongs to a class of antibiotics called cephalosporins and is used to treat infections caused by bacteria, including upper respiratory infections, ear infections, skin infections, and urinary tract infections. Just like Omnicef (cefdinir), Keflex works against a wide variety of bacterial pathogens but does not destroy their protective layer entirely thus allowing our immune system to effectively eradicate the infection. However, Keflex has been around for a longer period and its dosage schedule typically requires more frequent dosing than newer third-generation agents such as Omnicef. Therefore it might be preferred when dealing with sensitive strains or less severe manifestations of disease where high blood levels aren’t necessary.

How effective are both Omnicef and Keflex?

Both cefdinir (Omnicef) and cephalexin (Keflex) are commonly prescribed cephalosporin antibiotics with a long history of effectiveness in treating bacterial infections. Both were initially approved by the FDA within a short time period, Omnicef in 1997 and Keflex much earlier in 1971. They work by disrupting the formation of the bacteria's cell wall, causing it to rupture and thereby killing the bacteria.

A randomized, double-blind study conducted in 2000 compared these two drugs directly for their effectiveness at treating patients with community-acquired pneumonia; both medications showed similar efficacy rates as well as comparable safety profiles.[1] The study found no significant difference between patients taking either medication regarding resolution or improvement of symptoms.

In terms of side effects, cephalexin has been shown to cause fewer gastrointestinal disturbances than many other first-generation cephalosporins. It is also safe for use during pregnancy[2]. Cefdinir too has a favorable safety profile and only mild side effects such as diarrhea being reported most frequently[3].

As second-line treatment options after penicillin-class antibiotics for conditions like strep throat or otitis media (ear infection), both have proven effective over years of clinical use[4]. However, because they belong to different "generations" of cephalosporins — each generation having slightly different coverage against various types of bacteria — one may be chosen over another based on specific patient needs.

References:

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At what dose is Omnicef typically prescribed?

Oral dosages of Omnicef range from 300–600 mg/day, divided into one or two doses. However, studies have shown that for most bacterial infections in adults and adolescents, a dosage of 300 mg per day is adequate. In children (6 months to 12 years), the dose may start at 7mg/kg every 12 hours up to a maximum dose of 600 mg/day. The frequency can be adjusted after a few weeks if there is no response. The maximum dosage that should not be exceeded under any circumstance is 600 mg/day.

At what dose is Keflex typically prescribed?

Keflex treatment is typically initiated at a dosage of 250-500 mg every 6 hours or 500 mg every 12 hours, depending on the nature and severity of the infection. The dose can be increased to up to 4000 mg/day (4 grams), divided into four equal doses spaced evenly throughout the day. This maximum dosage may be considered if there's no adequate response after several days of treatment with lower dosages. As always, it's crucial that patients follow their healthcare provider's instructions when taking Keflex to ensure safety and effectiveness.

What are the most common side effects for Omnicef?

Common side effects of Omnicef and Keflex can include:

Diarrhea
Nausea or vomiting
Abdominal pain
Headache
Dizziness
Unusual tiredness (general weakness and fatigue)
Rash, itching, or hives on the skin
Vaginal yeast infection or oral thrush (yeast infection in the mouth)

It's important to note that while these are common side effects, everyone reacts differently to medications. If you experience any unusual symptoms or if these symptoms persist or worsen, please consult with your healthcare provider promptly.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Omnicef?

While both Omnicef (cefdinir) and Keflex (cephalexin) are cephalosporin antibiotics used to treat bacterial infections, they can have different side effects. Some potential serious side effects of these medications include:

Allergic reactions: Signs may include hives, difficulty breathing, or swelling in your face or throat.
Severe skin reaction: This could manifest as redness, blistering or peeling skin accompanied by a fever and sore throat.
Serious stomach issues: Persistent nausea/vomiting, severe abdominal pain.
Yellowing eyes/skin due to liver problems
Unusual tiredness
Dark urine
Easy bruising/bleeding

In rare cases, this medication may cause a severe intestinal condition called Clostridium difficile-associated diarrhea due to resistant bacteria. Symptoms can occur weeks after treatment has stopped.

If you notice any of these symptoms while taking either Omnicef or Keflex, stop using the medication immediately and consult with your healthcare provider. Be sure to report even mild symptoms such as diarrhea because antibiotic-associated diarrhea can lead to more severe conditions if left unchecked.

What are the most common side effects for Keflex?

Keflex, also known as cephalexin, may cause the following side effects in some patients:

A dry mouth or a sore throat
Diarrhea or mild nausea and vomiting
Stomach pain accompanied by loss of appetite
Headache with potential dizziness
Mild skin rash
Vaginal itching and discharge due to yeast infection (for women)

Please note that while these side effects are less common than those associated with Omnicef, any persistent issues should be reported to your healthcare provider. Serious but rare adverse reactions such as confusion, agitation, extreme fatigue or muscle joint pain should receive immediate medical attention. It's crucial to remember that this isn't an exhaustive list of potential side effects; drug responses can vary significantly among individuals.

Are there any potential serious side effects for Keflex?

Keflex, like any medication, can have side effects. Some of these are more serious and require immediate medical attention. Pay close attention to the following:

Signs of an allergic reaction or severe skin reaction: hives, itching, fever or chills
Difficulty breathing or swallowing, swelling in your face or throat
Unusual bleeding or bruising
Severe nausea or vomiting
Yellowing of the eyes or skin (jaundice), indicating potential liver problems
Confusion, agitation, hallucinations
Dizziness and seizures (convulsions)

If you experience any of these symptoms while taking Keflex, seek immediate medical help.

Contraindications for Omnicef and Keflex?

Both Omnicef and Keflex, along with other antibiotics, may cause a variety of side effects in some individuals. If you notice severe reactions such as intense stomach cramps, bloody diarrhea or signs of an allergic reaction (such as hives; difficulty breathing; swelling of your face, lips, tongue or throat), please seek immediate medical attention.

Neither Omnicef nor Keflex should be taken if you have had an allergic reaction to other cephalosporin antibiotics. Always inform your physician about any medications you are taking or allergies you have; it's critical that they know this information to avoid dangerous drug interactions or reactions. For people who are allergic to penicillin-type drugs caution is needed because cross-reactivity between these classes can occur.

Moreover, these antibiotics can interfere with the effectiveness of certain types of birth control methods so ensure that your doctor knows if you're using them before starting on either medication.

How much do Omnicef and Keflex cost?

For the brand name versions of these antibiotics:

The average price for a 10-day course (20 tablets) of Omnicef (300 mg) is approximately $580, which equates to about $29-$58 per day, depending on your dose.
On the other hand, a 10-day course (20 capsules) of Keflex (500 mg), costs around $30, working out to roughly $1.50/day.

Hence, if you are prescribed a higher dosage range for Omnicef (i.e., 600mg/day or more), then brand-name Keflex may be less expensive on a per-day treatment basis. However, please remember that cost should not be the primary factor in determining which antibiotic is best suited to treat your particular infection.

As far as generic options go:

Cefdinir, the generic version of Omnicef is available in packs starting from 10 and above with prices ranging between $15 - $45 for a typical 5 -10 day treatment plan. This translates into daily medication costs of approximately $1.50 - $4.50.
Cephalexin –the generic substitute for Keflex– can be purchased in quantities starting at ten with an approximate cost range lying between just under one dollar up to around two dollars per day depending on whether you're taking standard doses such as 250mg up to four times daily or even larger amounts if deemed necessary by your healthcare provider.

Popularity of Omnicef and Keflex

Cefdinir, also known as Omnicef, is a broad-spectrum antibiotic commonly used for treating bacterial infections. In 2020, it was estimated that about 5 million prescriptions were made for cefdinir in the US. Cefdinir accounts for around 11% of cephalosporin antibiotic prescriptions in the country and its use has seen a steady increase since its introduction.

On the other hand, cephalexin (also known by its brand name Keflex) is an older and more widely recognized antibiotic that belongs to the same family (cephalosporins). It was prescribed to approximately 7 million people in America in 2020. In terms of overall cephalosporin prescriptions within the USA, cephalexin holds nearly a quarter share at about 24%. Its prevalence has been largely stable over the past decade with only minor fluctuations noted.

Conclusion

Both Omnicef (cefdinir) and Keflex (cephalexin) are widely used antibiotics belonging to the cephalosporin class, with a long-standing record of combatting bacterial infections effectively. Their efficacy is backed by extensive clinical studies indicating that they successfully treat bacterial infections more than placebo treatments. Both drugs work by disrupting cell wall synthesis in bacteria, but their spectrum of activity varies.

Omnicef covers a broader range of pathogens including some Gram-negative bacteria making it often chosen for more complicated or unidentified bacterial infections, while Keflex has narrower coverage and is best suited for known susceptible pathogens like Streptococci species.

Both medications are available as generics which can result in significant cost savings particularly if paying out-of-pocket. It's also important to note that both may require an adjustment period where effects may not be immediately visible until sufficient levels have been reached in the body.

Their side effect profiles are similar; generally well-tolerated although gastrointestinal disturbances such as nausea or diarrhea can occur. As with all antibiotics, allergic reactions may happen so patients should seek medical help immediately if they notice any signs like rash, swelling or difficulty breathing after taking either medication.