Dr. Ranjeet Baral is a senior general physician, consultant cardiologist and senior aviation medical consultant. He has been working at Shahid Gangalal National Heart Centre (Bansbari) for the past 27 years and at Vayodha Hospital (Balkhu) for the past 13 years. In the past, he was employed at Norvic International Hospital (Thapathali) for 23 years. Dr. Barala shared with THT his insights on specific features as well as differences in the effectiveness among older and newer generations of antibiotics. Excerpts:
1. Is there anything such as resistance to antibiotics ?
Yes, there is resistance to antibiotics. It can occur simply because theconcerned bacteria has developed resistance to the bacteria in the long run orwhere the concerned patient is responsible when he/she has not taken the full course prescribed by his/her physician in the past or has misused the particular antibiotics excessively and developed resistance to it.
In the past, after antibiotics used in the treatment of contagious diseases like pneumonia, tuberculosis, gonorrhea, salmonellosis became less effective, it has become more difficult to treat such diseases. Due to antibiotics resistance, in addition to the prolongation of the concerned patient's hospital visit, his/her medical expenses and the resulting mortality rate have also increased.
2. What are the generations in antibiotics ?
First of all, let's not get confused by the meaning of generation of antibiotics. It's not like with computers' categorization, which means the later the generation the better the computer in all aspects.
Foremost, there are around 8 types of antibiotics:
• Penicillin
• Cephalosporins
• Sulphonamides
• Macrolides
• Tetracyclines
• Aminoglycosides
• Carbapenem
• Fluoroquinolones
It is the Cephalosporins which has been categorized into 5 generation types and not necessarily that the 5th is the best one.
Antibiotics are grouped together based on the type of bacteria they are most effective against and their range of effectiveness in combating bacteria. These groups are referred to as 'generations'. There are five generations of these. Each generation is effective against different types of bacteria. There are basically two types of bacteria namely, Gram + and Gram -.
Thus, the earlier mentioned cephalosporin antibiotics work against infections that are considered to treat easily while later generations are used for the treatment of more severe infections.
• The first generation of antibiotics are effective against the gram + bacteria and some types of gram - bacteria.
• The second generationof antibiotics were developed for both gram + and - but more for gram - bacteria.
• The third generation of antibiotics was developed primarily for gram - bacteria and those resistant to the first and second generation of antibiotics.
• The fourthgeneration of antibiotics cover both cases of gram + and – bacteria. They are reserved for severe cases, where the patient's immune system is weakened. It is given parental (injected), i.e., not oral.
• The fifth generation of antibiotics is an advanced generation where the concerned patient is resistant to all other antibiotics.
The first, second and third generation of antibiotics are again classified on the basis of being oral and parenteral (injected), while the fourth and fifth generation of antibiotics are only parenteral.
3. Can a patient who has barely or never taken any antibiotics in the past be cured of an ailment by use of antibiotics from a previous generation ? Or does it have to be from the newest one ?
Yes, he/she can be cured by the first generation of antibiotics, depending upon the type of infection the concerned person has been infected with. If it is a simple gram + infection who has never taken antibiotics, then no problem. However, if he/she has been admitted to a hospital for some other medical problem and develops a 'hospital acquired infection', then he/she will require a newer generation of antibiotics.
4. A patient was prescribed older generation antibiotics by a physician. It failed to do its job in the required time frame. Another physician stated that it was due to it being from an older generation. The patient was hoping to get a third perspective regarding this.
From the aforementioned aspects, it should be clear that the concerned patient was probably infected by a gram- or a resistant strain of bacteria, although the nature of his/her illness has not been stated. Bottom line, it's not necessary that one has to be treated by a fifth 'latest' generation antibiotic at the outset. It all depends on what is the nature of the concerning patient's infection, meaning it could have been skin, UTI (Urinary Tract Infection), URTI (Upper Respiratory Tract Infection), sepsis, STIs (Sexually Transmitted Infections), sepsis, pneumonia, etc.
However, since the concerned patient did not respond to the initial antibiotics course, it's obvious that he/she required at least the third-generation course. Depending on the case, he/she may require antibiotics from a fourth or fifth generation.
Any queries regarding heart disease, overall physical health or aviation medicine may be sent to dr.ranjeetbaral@gmail.com. The answers to these questions may be published as articles, retaining the senders' anonymity.