In this Article

• What is cephalexin (Keflex)?
• What are the possible side effects of cephalexin (Keflex)?
• What is the most important information I should know about cephalexin (Keflex)?
• What should I discuss with my healthcare provider before taking cephalexin (Keflex)?
• How should I take cephalexin (Keflex)?
• What happens if I miss a dose (Keflex)?
• What happens if I overdose (Keflex)?
• What should I avoid while taking cephalexin (Keflex)?
• What other drugs will affect cephalexin (Keflex)?
• Where can I get more information?

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

Do not use this medication if you are allergic to cephalexin, or to other cephalosporin antibiotics, such as:

• cefaclor (Ceclor);
• cefadroxil (Duricef);
• cefdinir (Omnicef);
• cefditoren (Spectracef);
• cefixime (Suprax);
• cefprozil (Cefzil);
• ceftazidime (Fortaz); or
• cefuroxime (Ceftin).

Before using cephalexin, tell your doctor if you are allergic to any drugs (especially penicillins), or if you have:

• kidney disease;
• liver disease;
• a stomach or intestinal disorder such as colitis;
• diabetes; or
• if you are malnourished.

If you have any of these conditions, you may need a dose adjustment or special tests to safely take cephalexin.

The oral suspension (liquid) form of cephalexin may contain sugar. This may affect you if you have diabetes.

FDA pregnancy category B. This medication is not expected to be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

Cephalexin can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take cephalexin (Keflex)?

Take the medication exactly as it was prescribed for you. Do not use the medication in larger amounts, or use it for longer than recommended by your doctor. Follow the instructions on your prescription label.

Take cephalexin with a full glass of water.

Dissolve the cephalexin dispersible tablet in a small amount of water, about 2 teaspoonfuls. Stir this mixture and drink all of it right away. To make sure you get the entire dose, add a little more water to the same glass, swirl gently and drink right away. Do not swallow or chew a dispersible tablet.

Shake the oral suspension (liquid) well just before you measure a dose. To be sure you get the correct dose, measure the liquid with a marked measuring spoon or medicine cup, not with a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

Take cephalexin for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. Cephalexin will not treat a viral infection such as the common cold or flu.

This medication can cause you to have unusual results with 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 and heat.

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