Obesity doesn't mean increase in one's size alone. It will also demand higher dosage of antibiotics and antimicrobial medications, says a study by doctors from Greece and the US. The accompanying editorial in Lancet also endorses the approach.
Whereas children's antibiotic dosing is generally calculated according to body mass, for adults, no such system is in place, and for those drugs that do have body mass specific guidelines for dosing, adherence is "inadequate," according to the authors. Drs. Matthew E. Falagas and Drosos Karageorgopoulos of the Alfa Institute of Biomedical Sciences in Athens point out that, under current practices, a 200 lb., 6'2" man (90kg, 1.9m) diagnosed with pneumonia would receive the same dose of antibiotics as a 124 lb., 5' woman (56kg, 1.5m) with the same condition, despite their dramatically different body sizes. While dosage according to body mass is standard in anesthetics, pediatrics, oncology and other fields, when it comes to antibiotics and antimicrobials the dosing guidelines are too broad, the authors argue, and may undermine a medications efficacy.
The editorial states, "Many medical disorders can lead to increasing or decreasing bodyweight and in view of the growing obesity epidemic in some countries and rising rates of under-nutrition in others, it follows that taking a patient's bodyweight into account makes pharmacological and clinical sense. Adjusting drug doses according to body weight might not only be more clinically effective, but also be more tolerable for patients since they might have fewer side-effects. If bodyweight is to become a major consideration in clinical treatment, could similar drug-dosing principles be applied to all medicines, not just toxic agents and anti-infective agents? Relevant randomised controlled trials are needed to adequately answer this question.
"Doctors might be willing to implement the practice of adjusting treatment for an individual's body weight if robust clinical trials showed benefits to their patients. Since doctors often prescribe via computer, appropriate algorithms could easily be incorporated—as in paediatric practice, in which dose adjustment can be made fairly easily by the use of liquids and solutions."
It is true such forms of treatment are often expensive and have a limited shelf-life. So when evidence points to the therapeutic advantages of dose adjustment per bodyweight, a wider range of tablet strength options would need to be widely available, the editorial notes and wonders, cheekily, "Good for pharmaceutical business perhaps?"
Professor Steve Field, chair of the Royal College of GPs, London, said he would encourage "appropriate" antibiotic prescribing and lots of patients are given them unnecessarily.
But he said: "Patients are getting taller and larger and it does seem right that patients are given the appropriate strength of drug.
"However, this might cost a lot of money because pharmaceutical companies would have to provide different doses of medication.
"At the moment, most come in two strengths and we would not want to see an increase in costs."
He added that GPs will already use their judgment to alter medication doses where necessary.