Klacid (Clarithromycin)
Complete patient guide for uses, dosage, side effects, and safety information
Prescription RequiredQuick Facts
What Is Klacid Used For?
Klacid contains clarithromycin, an antibiotic that belongs to a group of medicines called macrolides. These medicines work by killing or stopping the growth of bacteria that cause infections.
Primary Uses
Klacid is used to treat bacterial infections including respiratory tract infections (throat, airways and lungs), ear infections, skin infections, and peptic ulcer. It is also used to prevent a specific bacterial infection associated with HIV infection.
How It Works
Klacid works by killing or stopping the growth of bacteria which cause infections. It will not work against infections caused by viruses, such as colds or flu. For peptic ulcers, it treats the Helicobacter pylori (H. pylori) bacteria infection that is associated with nearly all peptic ulcers.
Good to know: Klacid will not work against viral infections like colds or flu – it only treats bacterial infections
How to Take Klacid
Take Klacid exactly as directed by your doctor. The dose will depend on the infection being treated and may differ from general recommendations.
Dosage Instructions
For respiratory tract and skin infections, the usual adult dose is one 250 mg tablet twice daily. For more severe infections, this can be increased to one 500 mg tablet twice daily. For children, the usual dose is 7.5 mg/kg twice daily. Tablets should be swallowed whole with water. The liquid form should be shaken well and measured accurately. Take at about the same time each day, with or without meals.
What If You Miss a Dose?
If it’s almost time for your next dose, skip the missed dose and take your next dose when scheduled. Otherwise, take it as soon as you remember, then continue normally. If you miss more than one dose, check with your doctor or pharmacist.
Important: Never take a double dose to make up for a missed dose
Available Tablet Strengths
Side Effects
Like all medications, this medicine can cause side effects. Most are mild and temporary, but some require medical attention.
Common Side Effects
These side effects occur relatively frequently and usually don’t require emergency care:
- stomach cramps and pains
- nausea, vomiting and diarrhoea
- oral thrush or vaginal thrush
- change in taste sensation
- headache
- asthma, shortness of breath
- muscle weakness, pain or spasms
- conjunctivitis
- chills
- fatigue
- belching
- stomach bloating
- flatulence
Seek immediate medical attention if you experience:
- yellowing of eyes or skin (jaundice)
- feeling generally unwell with poor appetite
- hearing disturbances
- chest pain
- dizziness, confusion, hallucinations, convulsions
- fainting, irregular heartbeat
- skin rash, itching, hives
- severe diarrhoea, especially if bloody
- severe upper stomach pain with nausea and vomiting
- swelling of face, lips, mouth, throat or neck causing difficulty swallowing or breathing
- sudden collapse
Important Warnings
There are several important conditions and situations where Klacid should not be used or requires special caution.
Who Should Not Take Klacid
Do not take if you are allergic to clarithromycin, other macrolide antibiotics (erythromycin, roxithromycin, azithromycin), have severe liver problems with poor kidney function, irregular heartbeat, long QT syndrome, low magnesium or potassium levels, or are taking certain medications including astemizole, terfenadine, cisapride, colchicine, domperidone, ergotamine, ivabradine, lomitapide, lovastatin, simvastatin, midazolam tablets/syrup, pimozide, ticagrelor, or ranolazine.
Medical Conditions to Discuss
Tell your doctor if you have heart problems (including slow heart rate), liver problems, poor kidney function, myasthenia gravis, sugar intolerance, electrolyte imbalances, or allergies to other medicines, foods, dyes or preservatives.
Pregnancy and Breastfeeding
Check with your doctor if you are pregnant, planning to become pregnant, or breastfeeding. Your doctor will discuss the risks and benefits of taking Klacid during pregnancy or while breastfeeding.
Drug Interactions
Many medicines can interact with Klacid, affecting how it works or how other medicines work. Always tell your doctor about all medicines you are taking.
- aminoglycosides (infection treatment)
- calcium channel blockers (verapamil, amlodipine, diltiazem)
- epilepsy medicines (carbamazepine, phenytoin, phenobarbital, sodium valproate)
- immune system medicines (ciclosporin, tacrolimus)
- heart medicines (digoxin, quinidine, disopyramide)
- antifungal medicines (fluconazole, itraconazole)
- antidepressants (fluoxetine)
- St John’s Wort
- cancer medicines (ibrutinib, vinblastine)
- diabetes medicines (insulin, nateglinide, repaglinide, pioglitazone, rosiglitazone)
- HIV medicines
- antimalarial medicines (hydroxychloroquine, chloroquine)
- corticosteroids (methylprednisolone)
- stomach medicines (omeprazole)
- psychiatric medicines (quetiapine)
- infection medicines (rifabutin, rifapentine, rifampicin)
- erectile dysfunction medicines (sildenafil, tadalafil, vardenafil)
- cholesterol medicines (atorvastatin, rosuvastatin)
- asthma medicines (theophylline)
- bladder medicines (tolterodine)
- anxiety/sleep medicines (triazolam, alprazolam, midazolam)
- blood thinners (warfarin, apixaban, dabigatran, rivaroxaban, edoxaban)
Alcohol & Driving
Be careful when driving or operating machinery until you know how Klacid affects you.
Driving and Operating Machinery
Be careful before you drive or use any machines or tools until you know how Klacid affects you.
Storage
Keep Klacid tablets in a cool dry place below 25°C and protected from light. Keep tablets in their original pack until use. For the liquid form, store in a cool dry place below 30°C and protected from light. The prepared liquid can be used for up to 14 days when stored below 30°C. Do not refrigerate the liquid. Keep away from moisture, heat, sunlight, and out of reach of children.
Overdose Information
If you think you have taken too much Klacid, seek immediate medical attention. Contact the Poisons Information Centre (Australia: 13 11 26), your doctor, or go to the nearest hospital emergency department, even if you feel fine. Taking too much may cause severe stomach problems, liver issues, or allergic reactions.
Frequently Asked Questions
Keep taking Klacid until you finish the pack or for as long as your doctor tells you. For infections, it’s usually taken for one or two weeks. Don’t stop early even if you feel better, as your infection may not clear completely.
Yes, the liquid form can be taken with or without meals and can be taken with milk. The tablets should be swallowed whole with water.
If you’re taking Klacid for an infection and your symptoms don’t improve within a few days or become worse, tell your doctor immediately.
No, never give Klacid to anyone else, even if their symptoms seem similar to yours. Each person needs their own prescription based on their specific condition.
Call your doctor straight away if you get severe diarrhoea, even if it occurs several weeks after stopping Klacid. This may indicate a serious bowel condition requiring urgent medical care. Don’t take anti-diarrhoea medicine without checking with your doctor first.
The prepared liquid suspension can be used for up to 14 days when stored below 30°C. Do not refrigerate it. Discard any unused suspension after 14 days.
No, Klacid will not work against infections caused by viruses, such as colds or flu. It only treats bacterial infections.
Important Disclaimer
This information is intended for general educational purposes only and should not be considered medical advice. Always consult your healthcare provider or pharmacist before starting, stopping, or changing any medication.
If you think you may have a medical emergency, call your doctor or emergency services immediately.