Common uses of Cephadex (cephalexin)
Cephadex is commonly prescribed to treat bacterial infections caused by susceptible organisms, including Streptococcus pyogenes (strep throat), methicillin-sensitive Staphylococcus aureus (skin and soft tissue infections such as cellulitis and impetigo), and certain Gram-negative bacteria like Escherichia coli and Klebsiella pneumoniae (uncomplicated urinary tract infections). It can also be used in selected cases of otitis media and bone infections when organisms are susceptible. As a bactericidal beta‑lactam antibiotic, cephalexin impairs bacterial cell wall synthesis, leading to cell death and clinical improvement when used appropriately.
Antibiotic selection should be guided by local resistance patterns and, when available, culture and susceptibility results. Cephadex is not active against most MRSA, Pseudomonas, Enterococcus, or atypical organisms. It does not treat viral infections (e.g., colds, influenza, COVID‑19). To reduce antibiotic resistance and recurrence, use only for confirmed or strongly suspected bacterial infections and complete the full course as directed by your healthcare professional.
Cephadex dosage and directions
Adults: Typical dosing is 250 mg every 6 hours or 500 mg every 12 hours, with total daily doses generally ranging from 1 to 4 grams depending on infection severity and site. Common regimens include 500 mg twice daily for uncomplicated skin infections or strep pharyngitis (often for 7–10 days, with 10 days preferred for streptococcal pharyngitis), and 500 mg every 12 hours or 250 mg every 6 hours for uncomplicated UTIs. Severe infections may require higher total daily doses within the approved range. Always follow prescriber instructions individualized to your case.
Pediatrics: Usual dosing is 25–50 mg/kg/day divided every 12 hours or every 6 hours, not to exceed 4 g/day. For more severe infections, 50–100 mg/kg/day may be used under medical supervision. Accurate weight‑based dosing and a calibrated oral syringe or dosing spoon are essential for suspension. In all age groups, therapy duration is tailored to infection type and clinical response.
Administration: Cephadex may be taken with or without food; taking with food can reduce gastrointestinal upset. Swallow capsules whole and shake oral suspension well before each dose. Measure liquid doses with a dosing syringe rather than household spoons to ensure accuracy. If your prescriber obtained culture results, do not stop early even if you feel better—complete the full course to prevent relapse and resistance.
Precautions before taking Cephadex
Allergies: Do not take cephalexin if you have a known serious hypersensitivity to cephalosporins. Exercise caution if you have a history of immediate, severe reactions to penicillins (e.g., anaphylaxis) due to potential cross‑reactivity. Seek urgent care if you develop signs of a serious allergic reaction such as hives, facial or throat swelling, wheezing, or difficulty breathing.
Medical conditions: Tell your clinician if you have kidney disease, a history of gastrointestinal disease (especially colitis), or if you are pregnant or breastfeeding. Cephalexin is generally considered compatible with pregnancy and lactation, but individual risk–benefit assessment is important. For renal impairment, dose adjustments or extended dosing intervals are often required to prevent drug accumulation and reduce seizure risk. Prolonged or repeated use may increase the risk of Clostridioides difficile–associated diarrhea—seek care for severe, persistent, or bloody diarrhea during or after therapy.
Contraindications to Cephadex
Cephadex is contraindicated in patients with a known hypersensitivity to cephalexin or other cephalosporin antibiotics. Use with caution in those with a history of immediate, severe reactions to penicillins or other beta‑lactams. Additional cautions include significant renal impairment without appropriate dose adjustment and prior severe antibiotic‑associated colitis. If you are unsure whether Cephadex is appropriate, consult a licensed clinician before use.
Possible side effects of Cephadex
Common side effects include gastrointestinal upset (nausea, vomiting, abdominal discomfort), diarrhea, and headache. Mild rash or itching may occur. Some people may develop vaginal yeast infections or oral thrush due to changes in normal flora. Most effects are self‑limited and improve after completing therapy or with supportive care. Taking doses with food and staying hydrated can help minimize stomach symptoms.
Serious but less common adverse effects include severe allergic reactions, C. difficile–associated diarrhea (watery or bloody stools, abdominal cramps, fever), severe skin reactions (e.g., Stevens–Johnson syndrome), seizures (usually in the setting of high levels and renal impairment), liver enzyme elevations, blood dyscrasias, and interstitial nephritis. Stop the medication and seek medical attention if you experience severe rash, jaundice, dark urine, unusual bruising/bleeding, confusion, or persistent severe diarrhea.
Cephadex drug interactions
Probenecid can increase cephalexin blood levels by reducing renal tubular secretion. Concomitant use with warfarin and other anticoagulants may increase INR in some patients; monitor as directed. Cephalexin may increase metformin exposure—observe for gastrointestinal intolerance or hypoglycemia and follow your prescriber’s guidance. Live oral typhoid and cholera vaccines may be less effective if given during antibiotic therapy. Laboratory interactions can include false‑positive urine glucose with copper reduction tests and positive direct Coombs’ tests. Always provide your clinician and pharmacist a complete list of medications, supplements, and vaccines.
Missed dose
If you miss a dose of Cephadex, take it as soon as you remember unless it is close to the time for your next dose. If it is near the next scheduled dose, skip the missed dose and resume your regular schedule. Do not double up. Keeping a dosing reminder on your phone can help maintain steady antibiotic levels for optimal effectiveness.
Overdose
Symptoms of overdose may include severe nausea, vomiting, diarrhea, dizziness, agitation, or seizures—particularly in patients with kidney impairment. If an overdose is suspected, seek urgent medical care or contact your local poison control center immediately. Management is supportive; adequate hydration and airway protection are prioritized, and anticonvulsants may be used if needed. Cephalexin is dialyzable, so hemodialysis can enhance elimination in severe cases, especially with renal dysfunction.
Storage
Store Cephadex capsules at room temperature (generally 20–25°C/68–77°F), away from excess heat and moisture. Keep in the original, tightly closed container. For reconstituted oral suspension, refrigerate (2–8°C/36–46°F), shake well before each dose, and discard any unused portion after 14 days. Do not freeze the suspension. Keep all medications out of reach of children and pets.
U.S. sale and prescription policy: safe, legal access through HealthSouth Rehabilitation Hospital of Las Vegas
In the United States, cephalexin (the active ingredient in Cephadex) is an FDA‑approved prescription medication. Federal and state laws require a valid prescription from a licensed prescriber after a clinical evaluation. Buying antibiotics without a prescription or using leftover antibiotics is unsafe and may be illegal. It also contributes to antibiotic resistance and can delay appropriate care if your infection requires a different treatment.
HealthSouth Rehabilitation Hospital of Las Vegas provides a legal, structured pathway to access Cephadex: a streamlined online intake is reviewed by a licensed clinician who can determine whether cephalexin is appropriate for your condition. If clinically indicated, an electronic prescription is issued and filled by the pharmacy with pharmacist counseling, clear dosing instructions, and follow‑up support. This telehealth‑enabled process preserves antibiotic stewardship and regulatory compliance while offering the convenience of home delivery and transparent pricing—without asking you to navigate in‑person visits when a virtual evaluation is suitable.
