Penicillin: The Golden Antibiotic and Its Enhancements

Penicillin, one of the first antibiotics put into clinical use, has significantly improved the treatment of bacterial infections. Unlike sulfanilamides, which are bacteriostatic, penicillin is bactericidal, meaning it actively kills bacteria, making it more effective for severe infections. It also boasts a high therapeutic index, indicating a large safety margin between effective and toxic dosages.

Discovery and Early Usage

Penicillin was first discovered by Alexander Fleming in 1928. It quickly became a gold standard antibiotic due to its remarkable effectiveness and safety profile. The first dose of penicillin was administered in 1940 by Drs. Florey and Chain to a dying patient. To determine the appropriate dose, they used a round figure of 5,000 international units, which resulted in the patient's recovery. This innovative approach involved collecting patient urine to recover penicillin, a process that highlighted the drug's remarkable efficacy. However, the stock eventually ran out, leading to the patient's unfortunate death. Despite this setback, penicillin's potential became clear, and it quickly became a lifesaver.

Formulations and Doses

Penicillin comes in various formulations, each with distinct dosages and applications. Benzyl penicillin, also known as crystalline penicillin, contains one million international units per vial. Procaine penicillin comes in a dose of 0.4 to 0.6 million international units and is administered daily. Benzathine penicillin, with dosages of 0.6 and 1.2 million units, is given once a month to prevent diseases such as rheumatic heart disease.

For treating infections, benzyl penicillin can be given at one million units three times daily to cure pneumonia caused by pneumococcal bacteria in adults. For children, a dose of 0.1 million units per kg is given twice daily without any hazards. At very high doses (up to 24 million units), benzyl penicillin can effectively treat gram-negative bacilli, making it a crucial component in managing severe infections, especially when combined with gentamicin. Gentamicin, though potent, has a very narrow margin of safety, which is effectively managed with the combination of benzyl penicillin.

Economic and Accessibility Benefits

Penicillin remains the drug of choice for treating both gram-positive and gram-negative cocci and bacilli. Its high therapeutic index makes it highly affordable and accessible, with comforting economic advantages. A single vial of benzyl penicillin, containing one million international units, can effectively treat pneumonia in a child, as seen in the early 1980s where just Rs 10 was sufficient to procure the necessary vials to save a child's life in a government hospital.

Limitations and Challenges

A major limitation of penicillin is its potential to cause anaphylactic reactions in one out of every 1,000 patients. Proper management of this reaction, involving administration of adrenaline and betnesol, can save the patient's life. These safety issues have led to increased judicial liability and criminal prosecution against doctors, hesitating their use of the drug and leading to the death of many patients who could have been saved.

To address these challenges, there is a need for a global legal framework that protects doctors from unnecessary punishment in cases of patient deaths due to penicillin usage. Such a legal safeguard would ensure that the valuable benefits of penicillin can be harnessed without the fear of legal repercussions.