Rephalex

Indications

Cephalexin is an antibiotic used to treat bacterial infections, including:

• Throat, ear and sinus infections, and chest infections such as bronchitis
• Skin and soft tissue infections, such as boils, infected wounds and cellulitis
• Urinary tract infections
• Bone and joint infections
• Dental infections

It does not work against viral infections such as colds or flu.

How It Works

It stops bacteria from building their cell wall, so the bacteria break apart and die.

Dosage and Administration

Adults: usually 250 to 500 mg every 6 hours, or 500 mg every 12 hours, depending on the infection. For severe infections the doctor may give more, but not usually above 4 g a day. Children: the dose depends on body weight and must be given as prescribed.

It can be taken with or without food. Space doses evenly through the day and finish the full course, even if you feel better. People with kidney problems may need a lower dose.

Interactions

• Metformin: Cephalexin can raise Metformin levels; blood sugar may need watching.
• Probenecid: raises Cephalexin levels.
• Warfarin: the blood-thinning effect may increase.
• Oral typhoid and cholera vaccines: antibiotics can make them less effective.
• Some urine sugar tests may give a false positive result.

Contraindications

Do not take it if you are allergic to Cephalexin or other cephalosporin antibiotics. Tell the doctor if you have ever had a serious allergic reaction to Penicillin or similar antibiotics.

Side Effects

Common: diarrhoea, nausea, stomach upset, indigestion and mild skin rash. Less common: dizziness, headache, tiredness, and vaginal thrush.

Get urgent medical help if you have:

• Swelling of the face, lips or throat, difficulty breathing, or a widespread itchy rash (serious allergic reaction)
• Blistering or peeling skin, or sores in the mouth
• Severe or bloody watery diarrhoea, during or after treatment
• Yellow skin or eyes, or dark urine

Pregnancy and Lactation

Cephalexin is commonly used in pregnancy when a doctor considers it needed. Small amounts pass into breast milk; it is generally considered suitable while breastfeeding, but watch the baby for diarrhoea, rash or thrush and tell the doctor.

Precautions and Warnings

• Tell the doctor about kidney disease, past bowel problems such as colitis, or any allergies.
• Long use can allow other germs, such as fungi, to grow.
• Do not share antibiotics or keep leftovers for later.

Overdose

Too much may cause nausea, vomiting, stomach pain and diarrhoea. Contact a doctor or hospital, especially for a child or a person with kidney problems.

Therapeutic Class

Antibiotic: first-generation cephalosporin.

Storage

Store below 30°C in a dry place, away from light and out of the reach of children. Mixed oral suspension: keep as the pack says (often in the fridge at 2 to 8°C) and discard after the stated number of days.