Difference Between Antibiotics and Painkillers

Antibiotics and painkillers are the commonly prescribed medication. Antibiotics, also known as antibacterials, are the drugs prescribed to eliminate bacterial infection from the body while painkillers are prescribed to relieve the pain. Both the mode of action and the indication of use are different in these two classes of drugs. Antibiotics acts on different targets of the bacterial cell walls to either eliminate them or to prevent them from reproducing. On the basis of the chemical class and the target of the action antibiotics are further divided in to various classes.

Painkillers are classified in many ways and may have very different mode and target of actions. There intensity of the action also varies with their class. Most commonly used are Non Steroid Anti Inflammatory Drugs (NSAIDS), which can be prescribed for inflammation with pain. Paracetamol is one of the popular painkiller.


As discussed above antibiotics are the antimicrobial drugs used against the infection. These drugs are powerful discovery in the history of medical science. First antibiotic discovered was Penicillin. After Penicillin many more were introduced in the recent past and have critical role in case of infectious diseases. Antibiotics are classified in different classes like aminoglycosides, cephalosporins, glycopeptised, lipopeptides, macrolides etc. All have different targets on the microbes to work on. Some Antibiotics inhibits the cell wall synthesis, while some binds to ribosome to prevent the protein synthesis and some binds to the DNA gyrase enzyme to inhibit DNA replication and transcription. Antibiotics are to be chosen wisely as per the type of microorganism involved in the infection as there are strong chances of developing resistance for the drug.


Painkillers are classified in to 5 classes i.e. NSAIDS, COX-2 inhibitors, Opiates and Morphinomimetics, Flupirtine and specific agents. The first class also includes Paracetamol however the mechanics of its action is still unknown unlike the other members of the class which acts on cyclooxygenase leading to its inhibition. This results in decreased production of prostaglandin production and relieve in the pain and inflammation. COX-2 inhibitors also acts on the cyclooxygenase, however they are more specific for its COX-2 variant which is directly associated with analgesic action. These are more superior to NSAIDS as NSAIDS inhibits COX-1 as well resulting in more adverse effects. Opiates are derivatives of Morphine and Opiate Receptors which are situated in brain and all over the body. These are the strongest painkillers however have high risks of dependence and tolerance. Nowadays many synthetic drugs are available in the market which mimic the action of morphine hence called as morphinomimetics. Flupirtine opens K+ channel of the muscles by acting on central nervous system. It is used for moderate to severe pain. It is superior to Opiates as it does not have dependence and tolerance does not develop. Some of the specific agents like Nefopam, amytriptyline, carbamezepine are also used to relieve pain however the mechanism of action is unknown.

Difference between Antibiotics and Painkillers

Antibiotics are prescribed for the infection with painkillers and anti-inflammatory agents to relieve the pain and inflammation involved in infection. These can be given to the patients for prophylaxis of the infection who had undergone the surgery along with the painkillers. Both Antibiotics and the Painkillers belong to different sets of the drugs due to their indication of use chemical composition and the mechanism of action. These might be prescribed concurrently as written above but the reason for prescription remains different.


Antibiotics treat the patient by killing or limiting the micobs while painkiller calm the patient and relieves it from the pain. There are different classes of the drugs and might be used simultaneously in some cases when condition demands. Both can be prescribed simultaneously keeping the drug interaction in mind.