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Keflex

side effects drug center keflex (cephalexin) drug - patient side effects and images

Keflex Patient Information Including Side Effects

Generic Name: cephalexin

What is cephalexin?

Cephalexin is a cephalosporin (SEF a low spor in) antibiotic that is used to treat bacterial infections of the lungs, ear, skin, bones, bladder, and kidneys.

Cephalexin is used to treat infections in adults and children who are at least 1 year old.

Cephalexin may also be used for purposes not listed in this medication guide.

What are the possible side effects of cephalexin?

Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).

Call your doctor at once if you have:

  • severe stomach pain, diarrhea that is watery or bloody (even if it occurs months after your last dose);
  • unusual tiredness, feeling light-headed or short of breath;
  • easy bruising, unusual bleeding, purple or red spots under your skin;
  • a seizure;
  • pale skin, cold hands and feet;
  • yellowed skin, dark colored urine;
  • fever, weakness; or
  • pain in your side or lower back, painful urination.

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about cephalexin?

You should not use this medicine if you are allergic to cephalexin or to similar antibiotics, such as Ceftin, Cefzil, Omnicef, and others. Tell your doctor if you are allergic to any drugs, especially penicillins or other antibiotics.

Keflex Patient Information including How Should I Take

What should I discuss with my healthcare provider before taking cephalexin?

You should not use this medicine if you are allergic to cephalexin or any other cephalosporin antibiotic (cefdinir, cefadroxil, cefoxitin, cefprozil, ceftriaxone, cefuroxime, Omnicef, and others).

Tell your doctor if you have ever had:

The liquid form of cephalexin may contain sugar. This may affect you if you have diabetes.

Tell your doctor if you are pregnant or breast-feeding.

How should I take cephalexin?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Do not use cephalexin to treat any condition that has not been checked by your doctor.

Measure liquid medicine carefully. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

Use this medicine for the full prescribed length of time, even if your symptoms quickly improve. Skipping doses can increase your risk of infection that is resistant to medication. Cephalexin will not treat a viral infection such as the flu or a common cold.

Do not share cephalexin with another person, even if they have the same symptoms you have.

This medicine can affect the results of certain medical tests. Tell any doctor who treats you that you are using cephalexin.

Store the tablets and capsules at room temperature away from moisture, heat, and light.

Store the liquid medicine in the refrigerator. Throw away any unused liquid after 14 days.

Keflex Patient Information including If I Miss a Dose

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include nausea, vomiting, stomach pain, diarrhea, and blood in your urine.

What should I avoid while taking cephalexin?

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, call your doctor before using anti-diarrhea medicine.

What other drugs will affect cephalexin?

Tell your doctor about all your other medicines, especially:

  • metformin; or
  • probenecid.

This list is not complete. Other drugs may affect cephalexin, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Where can I get more information?

Your pharmacist can provide more information about cephalexin.


Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
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