Check Keflex Availability Before Starting a Prescription Request
Keflex is the reference brand for cephalexin, a first-generation cephalosporin antibiotic. It was approved for susceptible bacterial infections affecting the respiratory tract, middle ear, skin and skin structures, bone, and genitourinary tract. It does not treat colds, influenza or other viral illnesses.
Sweetwater Medical Center transmits the submitted request through its pharmacy-assignment system. The assigned dispensing pharmacy validates the prescription, determines whether brand-name Keflex can be supplied, identifies the finished product, confirms the final price, and remains responsible for dispensing and shipping.
Keflex Brand and Prescription Details
| Medication | Keflex |
|---|---|
| Active ingredient | Cephalexin |
| Medication class | First-generation cephalosporin antibacterial |
| Dosage form | Oral capsules; historical brand labeling also includes powder for oral suspension |
| Reference strengths | 250 mg and 500 mg capsules |
| U.S. market status | FDA-approved reference brand listed as discontinued; not withdrawn for safety or effectiveness reasons |
| Manufacturer and NDC | Identified by the assigned pharmacy if remaining brand product can be supplied |
| Prescription status | Prescription required |
Keflex should not be assumed to be in stock because the reference brand is no longer routinely marketed in the United States. If substitution is authorized, the pharmacy may be able to dispense an FDA-approved cephalexin product instead.
Reference Cash Prices for Keflex Capsules
These published cash-price references apply to the discontinued brand presentation and do not confirm current inventory.
| Strength | Package | Reference price | Per capsule |
|---|---|---|---|
| Keflex 250 mg | 20 capsules | From $53.46 | From $2.67 |
| Keflex 500 mg | 20 capsules | From $63.05 | From $3.15 |
The assigned pharmacy confirms whether the prescribed brand or an authorized cephalexin alternative is available and provides the final amount before fulfillment.
Patients may provide an existing prescription, request an eligible prescription transfer or select a $20 online medical consultation with Cody R. Christensen, DO, where available. A clinician must first determine whether an antibiotic is indicated and whether Keflex or another treatment is appropriate.
Prescription, account and personal information is handled according to the Sweetwater Medical Center Privacy Statement.
From Online Keflex Request to Licensed Pharmacy Fulfillment
A patient looking to buy Keflex online must use a prescription-based pathway. Because the brand is discontinued in the U.S. market, a request does not guarantee that brand-name capsules can be obtained, and any substitution must follow the prescription and applicable pharmacy law.
Enter the Prescribed Keflex Request
Choose the prescribed strength, compact package and available delivery preference. Do not select a strength based on price or a previous infection.
Submit Location and Prescription Information
Provide the requested ZIP code and an existing prescription, request an eligible transfer or select an available medical consultation.
Receive a System-Assigned Pharmacy
The order system assigns an eligible partner pharmacy using the destination, pharmacy licensing, service coverage and ability to process the antibiotic request.
Complete Prescription and Product Review
The assigned pharmacy checks the prescription, determines product availability, confirms the final charge and provides the applicable dispensing and shipping options.
Why Brand Keflex May Be Replaced With Cephalexin
Keflex and cephalexin are not two different active ingredients: Keflex is the original brand name, while cephalexin is the medication name used for approved alternatives. FDA records place the reference Keflex products in the discontinued section, and current patient information notes that the branded product is no longer marketed.
This distinction matters when a patient searches for a Keflex prescription online. A prescriber may write for cephalexin or permit substitution, but the dispensing pharmacy must follow the actual prescription and state requirements. Capsule color, inactive ingredients, manufacturer, package and NDC can differ between products even when the active ingredient and labeled strength are the same.
If a prescription specifies “dispense as written,” the pharmacy cannot automatically replace the brand with another product. When the exact brand cannot be supplied, the pharmacy may contact the prescriber to discuss a clinically and legally appropriate option.
Which Infections Can Keflex Treat?
Cephalexin kills susceptible bacteria by interfering with bacterial cell-wall synthesis. Whether it is a suitable choice depends on the infection site, likely organism, local resistance patterns, allergy history and, when available, culture results. A familiar symptom such as painful urination or a sore throat is not enough by itself to identify the correct antibiotic.
- Respiratory tract infections caused by susceptible Streptococcus pneumoniae or Streptococcus pyogenes.
- Middle-ear infections caused by susceptible organisms listed in the prescribing information.
- Skin and skin-structure infections caused by susceptible Staphylococcus aureus or Streptococcus pyogenes.
- Bone infections caused by susceptible Staphylococcus aureus or Proteus mirabilis.
- Genitourinary infections, including acute prostatitis, caused by susceptible Escherichia coli, Proteus mirabilis or Klebsiella pneumoniae.
Keflex is not active against every organism that can cause these conditions. Methicillin-resistant staphylococci, enterococci, Pseudomonas and several other bacteria are generally not covered by cephalexin. Clinical evaluation is especially important when symptoms are severe, recurrent or worsening.
Keflex 250 mg and 500 mg Dosing Is Infection-Specific
The labeled adult regimen for cephalexin capsules is commonly 250 mg every six hours or 500 mg every 12 hours, usually for 7 to 14 days. This is general prescribing information, not an instruction for self-treatment. The prescriber chooses the dose and duration according to the infection, severity, patient age, kidney function and microbiology information.
| Dosing factor | Why it changes the prescription | What the patient should do |
|---|---|---|
| Infection and organism | Different sites and bacteria require different schedules or another antibiotic | Use Keflex only for the diagnosed or strongly suspected bacterial infection |
| Kidney function | Cephalexin is cleared mainly through the kidneys and may require dose reduction | Report kidney disease and recent renal test results when available |
| Age and body weight | Pediatric dosing is weight-based rather than copied from an adult regimen | Use the prescribed measuring device for liquid medication |
| Treatment response | Persistent fever, spreading redness or worsening pain may signal treatment failure or a complication | Contact the prescriber rather than increasing or extending the dose |
Capsules may be taken with or without food. Taking a dose with food may be easier on the stomach for some patients. Space doses as directed, and do not double a missed dose; if the next dose is near, skip the forgotten dose and resume the regular schedule.
Finishing Keflex and Knowing When Treatment Is Not Working
Patients often begin to notice symptom improvement after the antibiotic has had time to act, but the pace varies by infection. Feeling better is not a reason to save remaining capsules for a future illness or share them with another person. Take the medication for the duration directed by the prescriber.
A clinician should be contacted if symptoms fail to improve within the expected interval, return soon after treatment or become more severe. Urgent evaluation may be needed for rapidly spreading skin redness, high fever with confusion, breathing difficulty, inability to keep fluids down, severe flank pain or signs of sepsis.
Keflex Side Effects: Diarrhea, Rash and Serious Reactions
Diarrhea is the most frequently reported adverse reaction. Nausea, vomiting, indigestion, gastritis and abdominal pain can also occur. Vaginal yeast symptoms, genital itching, dizziness, fatigue or headache have been reported but are not experienced by every patient.
Stop the medicine and seek emergency care for trouble breathing, facial or throat swelling, widespread hives, blistering or peeling skin, or another severe allergic reaction. Contact a clinician promptly for watery or bloody diarrhea, abdominal cramps or fever during treatment or in the weeks after it ends because antibiotic-associated colitis can be serious.
A history of allergy to cephalexin, another cephalosporin or a penicillin should be reviewed before treatment. The nature and timing of a previous reaction matter; patients should not test a suspected allergy by taking leftover medication.
Kidney Function, Metformin and Other Keflex Precautions
Cephalexin exposure can rise when kidney function is reduced. Unadjusted cephalosporin doses have been associated with seizures in susceptible patients, particularly those with renal impairment. Older adults and people with known kidney disease may need a lower total daily dose or a longer interval between doses.
- Metformin concentrations may increase when it is taken with cephalexin, so monitoring may be appropriate.
- Probenecid reduces renal excretion of cephalexin, and concurrent use is not recommended in the prescribing information.
- Patients using anticoagulants or with renal or liver impairment, poor nutrition or a prolonged antibiotic course may require attention to prothrombin time.
- Cephalexin can interfere with some urine glucose tests and may contribute to a positive direct Coombs test.
Pregnancy, breastfeeding, colitis or other significant gastrointestinal disease should also be disclosed. Cephalexin passes into human milk; a clinician can weigh the need for treatment and appropriate infant monitoring.
Keflex With Food, Alcohol and Daily Medicines
Keflex can generally be taken without regard to meals. Alcohol is not listed as a direct contraindication in the cephalexin prescribing information, but it can worsen nausea, dizziness or dehydration and may make recovery from an infection more difficult. A patient who is acutely ill or experiencing side effects should avoid drinking and ask the prescriber or pharmacist for individualized advice.
Before patients order Keflex online, the medication review should include prescription drugs, nonprescription products, vitamins and supplements. This is particularly relevant for metformin, probenecid, anticoagulants and any medicine affected by kidney function.
Keflex Price Without Insurance and Brand Supply
The published Keflex price without insurance is substantially higher than many cephalexin alternatives, but the more important issue is whether any usable brand inventory can be located. The reference amounts at the top of the page are not a promise that a pharmacy can fill a brand-only prescription.
Patients comparing the Keflex 500 mg price should confirm the prescribed quantity, brand requirement and whether substitution is allowed. A lower cash price does not justify changing the antibiotic, strength, interval or duration selected for the infection.
Storage, Missed Doses and Accidental Overdose
Store capsules in their original tightly closed container at room temperature, away from excess heat and moisture. Refrigerate mixed liquid cephalexin, keep it tightly closed and discard any unused portion after 14 days. Use a medication take-back program for unneeded medicine rather than saving it for another illness.
For a missed dose, take it when remembered unless it is nearly time for the next scheduled dose; do not take two doses together. In the United States, call Poison Help at 1-800-222-1222 after a suspected overdose. Call 911 if the person collapses, has a seizure, cannot breathe or cannot be awakened.
Medical Disclaimer
This page provides general information about Keflex, cephalexin and the pharmacy-order process. It does not diagnose an infection, identify the responsible organism, choose an antibiotic or replace an individual prescription and treatment plan.
An online consultation does not guarantee that Keflex or cephalexin will be prescribed. Patients should not begin antibiotics from a previous prescription, change the dose, stop early or substitute another product without guidance from a qualified healthcare professional.
Frequently Asked Questions About Keflex
How much does Keflex cost without insurance?
Published references list about $53.46 for 20 Keflex 250 mg capsules and $63.05 for 20 Keflex 500 mg capsules. Because the brand is discontinued in the U.S. market, the assigned pharmacy must confirm both availability and the final price.
Can I get a Keflex prescription online?
An online clinician may prescribe an appropriate antibiotic after evaluating the infection and medical history. A consultation does not guarantee a Keflex prescription or brand availability.
What infections does Keflex 500 mg treat?
Keflex is labeled for certain susceptible respiratory, ear, skin, bone and genitourinary infections. The 500 mg strength is not appropriate for every infection, and the prescriber must determine the dose and schedule.
Can you drink alcohol while taking Keflex?
Cephalexin labeling does not list a direct alcohol interaction, but alcohol may worsen nausea, dizziness or dehydration. It is reasonable to avoid alcohol while ill or experiencing side effects and follow individualized advice.
How long does Keflex take to work?
Improvement often begins within a few days, but timing depends on the infection and bacterial susceptibility. Contact the prescriber if symptoms worsen or do not improve within the expected interval.
Related Keflex and Antibiotic Information
Medical References
Pharmacist Review of Keflex Medication Information
The medication information on this page, including Keflex brand status, approved indications, dosage range, prescription requirement, kidney-dose considerations, contraindications, interactions, adverse effects and urgent warnings, was reviewed by Jeffrey Collins, PharmD, Pharmacist — Wyoming Pharmacist License 3836; NPI 1255701884.
This review applies to the general medication information published on the page and does not authorize an individual prescription or confirm that brand-name Keflex is available. The assigned pharmacy remains responsible for prescription validation, finished-product identification, inventory, final pricing, dispensing and shipping.
Last pharmacist review: 08.11.2026.