Cefalexin is a broad-spectrum antibiotic, which means it is active against a wide variety of bacteria. It treats infections by killing or stopping the growth of the bacteria that cause them.
Before taking Cefalexin
Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking Cefalexin it is important that your doctor or pharmacist knows:
- If you are pregnant, trying for a baby or breast-feeding. Cefalexin is not known to be harmful to unborn babies; however it is important that your doctor knows if you are expecting a baby.
- If you have kidney problems.
- If you have ever had an allergic reaction to this or to any other medicine. It is particularly important that you tell your doctor if you are allergic to any other antibiotics (such as penicillin).
- If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, such as herbal and complementary medicines.
- If you have porphyria (this is a rare inherited blood disorder).
How to take Cefalexin
- Before you start this antibiotic, read the manufacturer's printed information leaflet from inside your pack. The leaflet will give you more information about the specific brand of cefalexin you have been given, and a full list of side-effects which you may experience from taking it.
- As a guide, it is usual to take 2-4 doses of cefalexin daily for 5-7 days; however, your doctor will tell you what dose is right for you and your dose will also be on the label of the pack to remind you. Your course of treatment may be for longer or shorter periods of time than this, so it is important that you take cefalexin exactly as your doctor has told you. If you are taking cefalexin to prevent urinary tract infections from recurring, you are likely to be prescribed just one dose daily, which you should take each evening. If you have been given cefalexin liquid medicine to give to your child, read the directions carefully to make sure you give the correct amount.
- You can take cefalexin before, during or after your meals.
- Space the doses evenly throughout the day. Keep taking this medicine until the course is finished unless you are told to stop. It is important to take the full course (even if you feel your infection has cleared up) in order to prevent the infection from coming back.
- If you forget to take a dose, take one as soon as you remember unless it is nearly time for your next dose. If it is almost time to take your next dose, skip the missed dose and take your next dose when it is due. Do not take two doses together to make up for a forgotten dose.
Can Cefalexin cause problems?
Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.
Important: if you experience any of the following symptoms, contact your doctor for advice straightaway:
- A severe skin rash.
- Jaundice (yellowing of your skin or the whites of your eyes), fever, and pain in your joints.
- Swelling of your tongue, mouth, or face.
- Severe diarrhoea.
If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.
Cefalexin side effects
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have any of these serious side effects:
- diarrhoea that is watery or bloody;
- seizure (convulsions);
- fever, sore throat, and headache with a severe blistering, peeling, and red skin rash;
- pale or yellowed skin, dark colored urine, fever, confusion or weakness;
- easy bruising or bleeding, unusual weakness;
- confusion, agitation, hallucinations (seeing things that are not there); or
- urinating less than usual or not at all.
- Less serious side effects may include:
- mild nausea, vomiting, diarrhoea;
- dizziness, tired feeling;
- joint pain; or
- vaginal itching or discharge.
What other drugs will affect Cefalexin?
Before using Keflex, tell your doctor if you are using any of the following drugs:
This list is not complete and there may be other drugs that can interact with Keflex. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.
How to store Cefalexin
- Keep all medicines out of the reach and sight of children.
- Store cefalexin tablets and capsules in a cool, dry place, away from direct heat and light.
- Store cefalexin liquid medicine in a refrigerator and do not use it after the expiry date shown on the label.
Pregnancy and breastfeeding
- Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
- This medicine is not known to be harmful when used by pregnant women. However, as with all medicines, it should be used with caution during pregnancy and only when considered essential by your doctor, particularly during the first trimester. Seek medical advice from your doctor.
- This medicine passes into breast milk. It should be used with caution in breastfeeding mothers and only if the expected benefit to the mother is greater than any possible risk to the nursing infant. Seek medical advice from your doctor.
If you have any more questions please ask your Pharmacist.
Remember to keep all medicines out of reach of children
Please Note: We have made every effort to ensure that the content of this information sheet is correct at time of publish, but remember that information about drugs may change. This sheet does not list all the uses and side-effects associated with this drug. For full details please see the drug information leaflet which comes with your medicine. Your doctor will assess your medical circumstances and draw your attention to any information or side-effects which may be relevant in your particular case.