Keflex 250 mg Capsules

Brand name

The drug is known under the trade name Keflex. This designation is fixed in pharmaceutical registries and is actively used to identify the drug in pharmacy chains, medical institutions and among health professionals. The drug has gained popularity due to its effectiveness in the fight against bacterial infections that require a reliable antibacterial effect. The name was chosen by the manufacturers to emphasize its belonging to a certain group of antibiotics, distinguishing it from other means with similar properties.

International Nonproprietary Name (INN)

The international nonproprietary name of this medicine is cephalexin. This term is accepted by the international community to designate the active substance that provides the therapeutic effect. Cephalexin belongs to the first-generation cephalosporins, known for their ability to inhibit the growth of bacteria. The name is standardized by the World Health Organization, which allows to unify the prescription and production of this drug in different regions of the world.

Form of release

The medication is available in several forms, which makes it convenient for use depending on the age of the patient and the specifics of treatment. The main options include:

• Capsules with dosages of 250 mg and 500 mg of the active substance, intended for oral administration by adults and older children.
• Tablets with 500 mg dosage, providing an alternative for convenient use.
• Powder for preparation of suspension for oral administration with a concentration of 125 mg/5 ml and 250 mg/5 ml after dilution, often used in pediatrics.

Each form is designed with specific use in mind: capsules and tablets are suitable for outpatient treatment, while suspension is convenient for children or patients with difficulty swallowing solid forms. The choice of form is determined by the doctor depending on the nature of the infection.

Composition

The main active substance is cephalexin, an antibiotic from the group of first-generation cephalosporins. Auxiliary components depend on the form of release. In capsules, the following are used:

• Microcrystalline cellulose - filler for uniform distribution of the active substance.
• Lactose monohydrate - an auxiliary substance to create mass.
• Magnesium stearate - a lubricating agent to facilitate production.
• Gelatin - the basis of the capsule shell.
• Titanium dioxide - colorant for the shell.

The tablets add croscarmellose sodium as a disintegrant and a film coating of hypromellose. The suspension contains sucrose for taste enhancement, flavorings (e.g., strawberry) and xanthan gum as a thickener. The formulation is balanced to ensure stability and efficacy.

Pharmacologic Properties

Pharmacodynamics

Keflex has bactericidal action by disrupting the synthesis of peptidoglycan in the cell wall of bacteria. It binds to penicillin-binding proteins, preventing the formation of a strong structure, which leads to lysis of microorganisms under the influence of osmotic pressure. The drug is active against Gram-positive bacteria such as Staphylococcus aureus (including penicillinase-producing strains), Streptococcus pneumoniae and Streptococcus pyogenes, as well as some Gram-negative pathogens, including Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis.

The mechanism of action provides rapid killing of susceptible bacteria, making the drug effective in acute infections. It demonstrates moderate resistance to beta-lactamases, which increases its value in cases where other antibiotics may be less effective. The effect occurs soon after the therapeutic concentration is reached, allowing control of the infectious process.

Pharmacokinetics

Absorption

After oral administration, the active substance is absorbed in the upper gastrointestinal tract, predominantly in the small intestine. The maximum concentration in plasma is reached in 1-2 hours. Bioavailability is about 90-95%, which provides high efficacy of the oral form. Meal intake slightly slows down absorption, but does not reduce the total absorption, which allows taking the drug independently of meals.

Distribution

The component is well distributed in the body, penetrating the skin, lungs, bones, urinary tract and soft tissues. Binding to plasma proteins is about 10-15%, which contributes to the free distribution of the active substance to the foci of infection. Concentration in urine significantly exceeds the minimum inhibitory concentration for most pathogens, which makes the drug particularly useful in infections of the urinary system.

Metabolism

Metabolism is minimal: more than 90% of the dose taken remains unchanged. A minor part undergoes metabolic transformations in the liver with the formation of inactive metabolites, which reduces the load on this organ.

Excretion

It is excreted predominantly through the kidneys (about 90-100% in unchanged form) by tubular filtration and tubule secretion. The elimination half-life is 0.5-1.2 hours in patients with normal renal function, but may increase in patients with impaired excretion. High concentrations in urine persist for 6-8 hours after administration.

Indications for Use

Keflex is indicated for the treatment of infections caused by sensitive microorganisms:

• Infections of the upper respiratory tract: pharyngitis, tonsillitis, otitis media.
• Infections of the lower respiratory tract: bronchitis, pneumonia.
• Infections of the urinary tract: cystitis, pyelonephritis.
• Infections of the skin and soft tissues: furunculosis, impetigo, cellulitis.
• Infections of the bones: osteomyelitis (as part of complex therapy).

The drug is often used in infections caused by staphylococci or streptococci, especially in cases of allergy to penicillins. Prescribing requires confirmation of the sensitivity of the pathogen.

Contraindications

The use of Keflex is prohibited in:

• Hypersensitivity to cephalosporins or penicillins.
• Severe allergic reactions to beta-lactam antibiotics in the anamnesis.
• Severe renal insufficiency without dose adjustment.

Cautiously prescribe in colitis, blood coagulation disorders or allergic history.

Method of Administration and Dosage

How to take

Capsules and tablets are taken orally, drinking enough water (150-200 ml), regardless of meals. Suspension is prepared by adding water to the mark on the bottle, shake before each use. Patients are advised to avoid lying down immediately after administration to prevent esophageal irritation.

Dosages for adults and children

Dosage is determined by the nature of the infection:

• Adults: 1-4 g/day divided into 2-4 doses, course 7-14 days.
• Children over 1 year of age: 25-50 mg/kg/day divided into 2-4 doses, maximum 4 g/day.
• Children under 1 year of age: suspension at a dose of 25-50 mg/kg/day, divided into 2-3 doses.

Dose adjustment for certain conditions

In renal failure:

• Creatinine clearance 10-40 mL/min: 250-500 mg every 8-12 hours.
• Clearance less than 10 mL/min: 250-500 mg every 12-24 hours.

Hepatic insufficiency does not require correction.

Side Effects

Unwanted reactions may include:

• Gastrointestinal: nausea, diarrhea, abdominal pain, candidiasis.
• Allergic: rash, itching, rarely - anaphylaxis.
• Hematologic: eosinophilia, neutropenia.
• Nervous: headache, weakness.

In case of serious manifestations, discontinue use and consult a physician.

Overdose

Symptoms of overdose

Exceeding the dose is manifested by nausea, vomiting, convulsions, confusion.

First aid measures

In overdose:

• Stop taking it.
• Rinse the stomach (within 1-2 hours).
• Provide hydration and symptomatic support.
• Seek medical attention.

Drug Interactions

Influence on the effects of other drugs

The medication may:

• Amplify the effect of anticoagulants (warfarin).
• Decrease the effectiveness of probenecid (slows excretion).

Compatibility with alcohol and food

Alcohol does not affect directly, but may worsen the condition in infection. Food has no significant effect on absorption.

Special Precautions

Use in pregnancy and breastfeeding

Keflex is acceptable in pregnancy for strict indications (category B). Penetrates into milk, lactation is suspended.

Effects on driving and operating machinery

Faintness or dizziness may affect the ability to drive machinery.

Particulars of use in the elderly and children

The elderly require monitoring of renal function. In children the drug is safe taking into account the dosage by weight.