An Antibiotic is a type of antimicrobial substance active against Bacteria. It is the most common type of antibacterial agent used to fight against bacterial infections and antibiotic medicines are widely used in the treatment and prevention of such infections. Antibiotics may either kill the bacteria or inhibits the growth to get rid of the infection. A limited number of antibiotics also possess antiprotozoal activity (like metronidazole to treat a number of parasitic diseases). Antibiotics are not effective against any viral infections such as common cold, flu or any fungal infections like scabies, skin rashes etc.

First antibiotic discovered was Penicillin by Alexander Fleming in 1941 and since then they have  revolutionized the treatment of bacterial infections in humans and animals. Penicillin was found effective against infections caused by different bacterial types like  Streptococci, Staphyllococci, Pneumococci, Gonococci,and Spirochaetes of Syphilis.

In this segment we are going to cover topics like  types usage side effects and resistance of Antibiotics.

Types of Antibiotics

  • There is a wider range of Antibiotics medicines, categorized in to certain groups to treat different types of bacterial infections.
  • Antibiotics are  categorized by their spectrum of activity- namely whether they are narrow-broad-,or extended-spectrum.
  • Narrow Spectrum agents like Penicillin affects primarily Gram positive Bacteria.
  • Broad Spectrum agents like Chloramphenicol Tetracycline affect both Gram Positive and some gram negative bacteria.
  • An extended spectrum antibiotic is result of chemical modification affects additional types of bacteria usually those that are gram negative.
  • The term Gram Positive and Gram negative bacteria are used to distinguish between bacteria having cell walls consisting of a thick layer of Peptidoglycan(a peptide-sugar polymer) and thin layer of peptidoglycan respectively.

Some most commonly used antibiotics are as follows-

  • Antibiotics are classified to certain group depending on their mode of actions and are the groups are AMinoglycosides,Cephalosporins,Chloramphenicols.Flouroquinolones Lincosamides Macrolides Nitrofurans Penicillins Tetracyclines and Miscellaneous.
  • Aminoglycosides like Gentamicin Tobramycin Chloramphenicol inhibit protein synthesis and use to treat bacterial infections of Respiratory Tracts,Urinary Tracts abdominal and Pelvic inflammations.
  • Chloramphenicol is  used to treat bacterial infections of eyes,ears,cystic fibrosis etc.
  • Cephalosporin like Cefotaxime,Ceftraixone Cephalexin Cefuroxime inhibits cell wall synthesis and use to treat bacterial infections of Respiratory tracts,Urinary tracts ,Abdominal infections Skin infections,Bone and Joints infections  Otitis Infections,Gonorrhea and Meningitis.
  • Flouroquinolones like Ciprofloxacin and Norfloxacin inhibits DNA synthesis and used to treat GTI,UTI,RTI,Skin infections,Eye infections,Bone and Joint Infetions Pneumonia Sinusitis,Anthrax etc.
  • Norfloxacin plays an important role in treatment of STDs caused by Neisseria gonorrhoeae and prostatitis.
  • LIncosamides like Clindamycin inhibits protein synthesis and used to treat Skin infections,Respiratory infections,Abdominal infections Acne and pelvic diseases.
  • Macrolides like Azithromycin,Erytromycin Clarithromycin also inhibits protein synthesis and used to treat RTI,STDs,COPDs, Pneumonia,OTItis infections etc.
  • Clarithromycin is also used to treat infections of STDs. Pertussis, Diptheria,Intestinal amebiasis,and infection in minor wounds.
  • NItrofurantoin inactivates essential cell components and used to treat Urinary tract infections.
  • Penicillins like ampicillin,amoxycillins,piperacillins etc  inhibits cell wall synthesis and used to treat infections of skin,wounds,meningitis,amebiaisis,tonsillitis gonorrhea etc.
  • Tetracyclins inhibits protein synthesis and used to treat infections like pneumonia,wounds,intestinal amebiaisis,rickettsia etc.
  • Miscellaneous antibiotics like Rifampicin Isoniazid etc are used to treat Tuberculosis.
  • Metronidazole is used to treat parasitic infections.
  • Trimethorpim and Sulphamethaxozole (Sulfonamides) is used to treat Wounds and UTI.
  • Vancomycin is used to treat infections resistant to tetracyclines and penicillins.

Usage of Antibiotics

  • Antibiotic medicines are used to treat bacterial infections to the humans and animals.
  • AS mentioned above, Antibiotics are categorized under several groups on the basis of their mode of actions and are used to treat bacterial infections caused to different parts of Body.
  • Almost all the category is common to treat certain infections of Respiratory Tracts Urinary tracts,Gastro Intestinal Tracts,Wounds,Eyes and ear infections but some specific antibiotics like Clarithromycin Nitrofurantoins are more specific to treat certain infections while Miscelleneaous antibiotics like Vancomycin is used to treat resistant against Penicillin and Tetracyclins.
  • Mostly people takes antibiotic medicines orally however in some cases, it can be administrated by injections or applied directly to the infected part of Body.
  • Antibiotics should be taken whole course as prescribed by the Doctor even after the patient notices improvement in the symptoms.
  • Stopping the course in middle increases the risk of bacteria to grow further or become resistant to that particular antibiotic and creates trouble in future if any infection occurs.

Side Effects of Antibiotics

  • The side effects of Antibiotics ranges from Minor to very severe. The most common side effects of Antibiotics are Skin Rashes, Diarrhea, Nausea, Yeast Infections, Sensitivity to Sunlight(in case of tetracyclines).
  • If antibiotics are taken for longer duration, it may lead to fungal infections of the mouth, Digestive tracts or Genital parts.
  • Some unusual side effects of Antibiotics are-
  • Low Platelet counts while taking Cephalosporins and Penicillins among others.
  • Severe aches and pains while taking Floroquinolones.
  • Hearing Loss while taking macrolides or Aminoglycosides.
  • Low Granulocytes WBCs while taking Penicillins.
  • Formation of Kidney Stones while taking Sulfonamides.
  • Most severe Side effects are-
  • Clostridium difficile infections that cause severe diarrhea that may lead to colon damage and sometimes to death.
  • Severe life threatening Allergic Reactions.

Antibiotic resistant infections

Antibiotics Do and Dont’s-

  • Take antibiotics only if you need them. Antibiotics are effective only against the bacterial infections like Whoping Cough,UTIS,Wounds,Critical Diseases,Throat infections etc and not effective in treatment of Viral or Fungal Infections.
  • Using Antibiotics in treatment of Viral infections may lead to Antibiotic resistance.
  • Take antibiotics only to the prescribed dose and complete the course as advised by your physician.
  • Do not stop taking antibiotics midway if you feel better and do complete the course recommended by your Doctor.

Antibiotic Resistance

  • Most of us have taken antibiotics at some point in our lives to treat bacterial infections.
  • Antibiotic resistance happens when bacteria adapt or evolve to survive antibiotic treatment and it can cause antibiotics to become less effective or ineffective to treat the infection.
  • If a person in infected from a bacterial infection, A doctor may prescribe antibiotics to cope with the bacterial infection. The antibiotic may either kill the bacteria or stops its growth.In some cases, The Infectious bacteria adapts or mutates in response to the antibiotic prescribed.This can cause the bacteria to no longer respond to that antibiotics. And making it resistant to that particular antibiotic.

The resistant strain of that mutated or adapted bacteria multiplies and since the resistant developed to the antibiotic,infected person may experience severe complications

How does Antibiotic resistance occur?

  • There are many possible adaptations or mutations that can occur within bacteria to help them resist antibiotics and these may include-
  • Resisting the access of the antibiotic– Bacteria may adapt to change or limit the number of  entryways in to the cell wall making it resistant to the antibiotic to enter.
  • Removing the antibiotic– Some Bacteria may use pumps in the cell walls to remove the antibiotic entering the cell.
  • Changing or Destroying the Antibiotic– By using certain enzymes or hormones, some bacteria   breakdowns the antibiotic making it ineffective.

Complications of Antibiotic Resistance

  • Antibiotic resistance may cause Drug to be ineffective or least effective to the bacteria making it harder to treat the infection. In some cases it become impossible to treat or cure the patient.
  • If a person has Antibiotic resistant bacterial infection, he may require costly and toxic alternative treatments.
  • To combat antibiotic resistance, one should avoid overdose of Antibiotic, Misuse of Antibiotic, and do not practice Poor infection management.
  • Patient should take prescribed antibiotic only till the Medical Practitioner recommends.
  • Do not use leftovers antibiotics.

Frequently Asked Questions-

What are the common infections treated by Antibiotics?

Some most common bacterial infections that are treated by using Antibiotics are-Acne, Bronchitis, Conjunctivitis, Otitis media, STDs, Skin and Soft tissue infections, Streptococcal pharyngitis, RTIs, UTIS, GTIs, Diarrhea etc.

Which are the most common Antibiotics used to treat Bacterial Infections?

Antibiotics are categorized on their mode of action on the bacterial cell and some most commonly used antibiotics are-Amoxicillin,Ciprofloxacin,Cephalexin,Doxycycline,Cefixime,Cefpodoxime,Amoxycillin,Amoxycillin Clavulanic Acid, Levofloxacin, Ofloxacin, Metronidazole Azithromycin and Trimethorpim Sulphamethoxazole.

In Traumatic cases, Cefuroxime and Linezolid are found to be most effective.

Are there any over the counter antibiotics?

  • Over the counter antibiotics(OTC) are those antibiotics which are not prescribed to take orally however are used over the skin topically to treat the infection
  • Some common Over the Top antibiotics are-
  • Neosporin (Neomycin,Polymyxin B,Bacitracin)
  • Polysporin (Bacitracin,Polymyxin B)
  • Triple Antibiotic ( Neomycin+Bacitracin+Polymyxin B)
  • Neosporin+Hydroxycorticosterone
  • There are some OTCs available to treat acne too that contains antibacterial benzoyl peroxide which also has mild drying effect for acne.Many products are found at Pharmacy as Gels,Lotions,Solutions,Foams,CleaningPads and Facial Scrubs

Can I take antibiotics with Alcohol?

Mixing moderate amount of alcohol with antibiotics usually does not lowers the antibiotic’s effectiveness but it may cause some serious side effects and hinders the body’s ability to heal itself.

However it is not recommended to take alcohol if one is taking antibiotics to treat or cure any infection as Alcohal lowers the immune response of body making it difficult to recover and also impacts the antibiotics action to the body.

Liver may also get damaged if certain antibiotics are taken with Alcohal.So its better to take the safest route by avoiding alcohol during any course of treatment.

Hope this article covers maximum queries related to Antibiotics and its usage.


Please enter your comment!
Please enter your name here

Exclusive content

Latest article

More article