Cephalexin

INSTRUCTIONS FOR MEDICAL USE OF THE MEDICINAL PRODUCT CEFALEXIN (CEFALEXIN)

Composition:

Active substance: cephalexin;

5 ml of the ready suspension contains 250 mg cephalexin in the form of cephalexin monohydrate;

Excipients: sodium saccharin, anhydrous citric acid, iron oxide yellow (E 172), guar gum, sodium benzoate (E 211), simethicone, sucrose, flavors: strawberry, apple, raspberry, tutti-frutti.

Pharmaceutical form. Granules for oral suspension.

Main physicochemical properties: granular powder of yellow-orange color. When the recommended amount of water is added, a yellow ochre-colored suspension is formed, with a characteristic fruity odor and a bitter-sweet taste.

Pharmacotherapeutic group. Antibacterials for systemic use. First-generation cephalosporins. Cephalexin. ATC code J01D B01.

Pharmacological properties.

Pharmacodynamics.

Cefalexin is a semi-synthetic broad-spectrum antibiotic. Gram-positive microorganisms are sensitive to cefalexin: staphylococci (coagulase-positive and penicillinase-producing strains), streptococci (except enterococci), pneumococci. Cefalexin is also active against Escherichia coli, Klebsiella spp., Proteus mirabilis.

Cefalexin is inactive against Enterococcus spp., Staphylococcus aureus (methicillin-resistant), Enterobacter spp., Haemophilus influenzae, Moraxella catarrhalis, Pseudomonas aeruginosa, Mycoplasma spp., Chlamydia spp., Legionella spp.

Pharmacokinetics.

Cefalexin is rapidly and almost completely absorbed after oral administration (more than 90%). The extent and rate of cefalexin absorption are practically independent of food intake. Peak serum concentration is reached within 60–90 minutes after administration. Cefalexin penetrates well into body tissues and fluids, including pericardial and pleural membranes. Only 10–15% of the active substance is protein-bound in plasma. The drug is primarily excreted unchanged in the urine. Cefalexin is removed during hemodialysis and peritoneal dialysis.

Clinical characteristics.

Indications.

Treatment of infections caused by microorganisms sensitive to cephalexin:

• Ear, nose, and throat organs and respiratory tract (pharyngitis, otitis media, sinusitis, tonsillitis, bronchitis, pneumonia);
• Urinary and genital systems (pyelonephritis, cystitis, urethritis, prostatitis, epididymitis, endometritis, vulvovaginitis);
• Skin and soft tissues (furunculosis, abscess, phlegmon, pyoderma, lymphadenitis);
• Bones and joints (osteomyelitis).

Contraindications.

Hypersensitivity to cephalosporins, penicillins, or other beta-lactam antibiotics, as well as to excipients of the medicinal product; porphyria; infections of the central nervous system (brain or spinal cord); initial treatment of severe generalized infections requiring parenteral cephalosporins.

Interaction with other medicinal products and other forms of interaction.

Due to the bactericidal action of cephalexin, it should not be combined with bacteriostatic antibiotics such as tetracyclines and chloramphenicol.

Nonsteroidal anti-inflammatory drugs (NSAIDs): may delay excretion of cephalex inflammatories.

When used concomitantly with highly active diuretics (ethacrynic acid, furosemide) or potentially nephrotoxic medicinal products (aminoglycosides, polymyxin, colistin, amphotericin, capreomycin, vancomycin), cephalosporins may increase nephrotoxicity.

Medicinal products that reduce platelet aggregation (nonsteroidal anti-inflammatory drugs, antiplatelet agents, vitamin K antagonists such as warfarin, sulfinpyrazone) may prolong prothrombin time and increase the risk of bleeding.

Probenecid and phenylbutazone reduce renal excretion of cephalexin, as well as other beta-lactam agents.

Concomitant use with probenecid or phenylbutazone may lead to increased plasma half-life and plasma concentration of cephalexin.

Cephalosporins may reduce the effectiveness of oral contraceptives; therefore, use of additional contraceptive methods is recommended.

Interaction between cephalexin and metformin may result in metformin accumulation. When cephalexin and metformin are administered concomitantly at a single dose of 500 mg, the Cmax and AUC of metformin increase on average by 34% and 24%, respectively, while renal clearance decreases by 14%.

In patients receiving cytotoxic therapy for leukemia, hypokalemia may develop with concomitant use of gentamicin and cephalexin.

Special precautions for use

Before initiating therapy, it is necessary to determine whether there is a history of hypersensitivity reactions to cephalosporins, penicillins, or other allergens.

Cross-allergic reactions between penicillins and cephalosporins are possible (5–10%). Severe hypersensitivity reactions (including anaphylaxis) have been reported with both drugs.

Cephalexin should be used with caution in patients predisposed to allergic conditions (e.g., hay fever, allergic diathesis) and/or bronchial asthma.

Prolonged use of cephalexin may lead to dysbiosis and superinfection (e.g., candidiasis).

Preventive measures should be taken if secondary infection occurs.

During treatment, regular monitoring of peripheral blood cell counts, liver function, and kidney function is recommended.

Cephalexin should be administered with caution in patients with severe renal impairment. Regular monitoring of renal function and dose adjustment are recommended.

When using nearly all broad-spectrum antibacterial agents, including macrolides, semisynthetic penicillins, and cephalosporins, pseudomembranous colitis may develop, ranging from mild to life-threatening. Therefore, if diarrhea occurs after antimicrobial use, it is important to rule out this condition.

If severe diarrhea characteristic of pseudomembranous colitis develops, the drug should be discontinued and appropriate measures initiated. The use of agents that inhibit peristalsis is contraindicated.

Treatment with cephalosporins (including cephalexin) may be associated with reduced prothrombin activity. Therefore, in patients with impaired vitamin K synthesis or deficiency (e.g., patients with chronic liver or kidney disease, cystic fibrosis, elderly patients, malnourished patients, or those who have undergone prolonged antibiotic therapy), as well as in patients who have received prolonged anticoagulant therapy prior to cephalexin administration, prothrombin time should be monitored and vitamin K administered if necessary.

The product contains sucrose; therefore, if you have been diagnosed with intolerance to certain sugars, consult your physician before taking this medicinal product.

A positive direct Coombs test result has been reported during treatment with cephalosporin antibiotics. A positive Coombs test may also be observed in newborns whose mothers received cephalexin during pregnancy.

When testing for glucose in urine during treatment with this medicinal product, a glucose oxidase test should be used, as other methods (e.g., Fehling's or Benedict's tests) may yield false-positive results.

Cephalosporins may interfere with urine ketone body testing results.

Use during pregnancy and breastfeeding

There are no adequate data on the teratogenic effects of the drug; it may be prescribed during pregnancy only after careful assessment of the benefit-risk ratio.

Cephalexin passes into breast milk; therefore, breastfeeding should be discontinued during treatment.

Ability to affect reaction speed when driving or operating machinery

Until individual response to the drug is established (dizziness and confusion may occur), caution is recommended when driving or operating machinery.

Dosage and Administration

Cephalexin is administered orally.

The usual daily dose for children (with body weight less than 40 kg) is 25–50 mg/kg of body weight (depending on the severity and site of infection), divided into 2–4 doses.

In severe cases, the dose may be doubled. For treatment of acute otitis media, the recommended dose is 75–100 mg/kg body weight, divided into 2–4 doses.

In most cases, the duration of treatment is 7–10 days. To prevent complications of streptococcal infections, the drug should be administered for at least 10 days.

Recommended pediatric suspension dosing

The usual daily dose for children from 14 years of age and adults is 1–4 g, which should be divided into 2–4 doses. For skin and soft tissue infections, streptococcal pharyngitis, and uncomplicated urinary tract infections, the usual dose is 250 mg every 6 hours or 500 mg every 12 hours. In severe cases, the dose may be doubled.

Dosing in renal impairment

For patients undergoing dialysis, administer 250 mg of the drug 1–2 times daily and an additional 500 mg after each dialysis session, resulting in a total daily dose of up to 1 g on dialysis days.

Preparation of the suspension.

Shake the bottle to detach the powder from the walls and bottom. To prepare 100 mL of suspension, add 74 mL of drinking water to the bottle containing the granules (up to the mark) and shake well. Shake thoroughly before each use.

The medicinal product should not be used during meals.

Children. The drug is used in pediatric practice.

Overdose.

Symptoms: nausea, vomiting, epigastric pain, diarrhea, hematuria, electrolyte imbalance, hyperreflexia, seizures.

Treatment: in case of overdose, clinical and laboratory monitoring of hematological, renal, hepatic functions and blood coagulation is required until the patient's condition stabilizes.

Gastric lavage should be performed if the usual dose is exceeded by 5–10 times.

Symptomatic treatment should be applied (administration of activated charcoal, hemodialysis).

Adverse Reactions.

Gastrointestinal system: nausea, vomiting, diarrhea, abdominal cramps/pain, decreased appetite/anorexia (usually resolves spontaneously even with continued use of the drug), dry mouth, dyspepsia, flatulence, gastritis, rarely colitis including pseudomembranous enterocolitis; with prolonged use, dysbacteriosis, candidal stomatitis, intestinal candidiasis, and anal pruritus may develop.

Hepatobiliary system: transient increase in hepatic transaminase activity (aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase), increased plasma bilirubin levels, transient toxic hepatitis, cholestatic jaundice.

Blood system: neutropenia, leukopenia, thrombocytopenia/thrombocytosis, eosinophilia, agranulocytosis, lymphopenia, pancytopenia, hemolytic anemia, aplastic anemia, prolonged prothrombin time, hemorrhages.

Immune system: hypersensitivity reactions, including allergic reactions in patients with known allergy to penicillins and cephalosporins; angioneurotic edema, rarely anaphylaxis (including bronchospasm, dyspnea, decreased arterial pressure, anaphylactic shock), anaphylactoid reactions, drug fever. Allergic reactions usually resolve after discontinuation of therapy.

Skin and subcutaneous tissue: skin rash, including erythematous rash, dermatitis, pruritus, skin hyperemia, urticaria, edema, including of the face and/or neck, hands and/or feet, erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis.

Nervous system: dizziness, vertigo, weakness, headache, excitation, confusion, hallucinations, possible seizures (especially in patients with renal insufficiency and unadjusted dosing).

Urinary and reproductive system: very rarely – reversible renal function impairment; possible manifestations of toxic nephropathy in patients with impaired renal function; isolated cases of interstitial nephritis. Reversible fever, increased blood urea nitrogen, hypercreatininemia, pyuria, and eosinophiluria are characteristic signs of cephalosporin-induced interstitial nephritis. Cases of acute tubular necrosis have also been reported.

Musculoskeletal system: joint involvement, arthralgia, arthritis.

Reproductive system: genital candidiasis, genital pruritus, vaginitis, vaginal discharge.

Other: increased fatigue, elevated serum lactate dehydrogenase (LDH) levels, false-positive Coombs test, false-positive urine glucose test.

Shelf life. 3 years.

Storage conditions. Store at a temperature not exceeding 25 °C in the original packaging to protect from light and moisture. After reconstitution, the suspension should be stored at a temperature not exceeding 25 °C for up to 14 days.

Keep out of reach of children.

Packaging.

40 g in a bottle; 1 bottle with a measuring spoon in a cardboard package.

Prescription status. Prescription only.

Manufacturer.

«Hemofarm» AD.

«Hemofarm» AD.

Manufacturer's address and location of business operations.

Beogradski put bb, 26300, Vrsac, Serbia.

Beogradski put bb, 26300, Vrsac, Serbia.