Your Health

Any antibiotic can have both risks and benefits. New studies warn against the abuse of antibiotics, indicating for example that just as Azithromycin could disrupt heart rhythm, similarly tetracycline may reduce male fertility, reports Sade Oguntola.

If a runny nose and congested chest make one to think of antibiotics, think again. Antibiotics are powerful medicines that fight bacterial infections. Antibiotics can be lifesavers but its hazards when misused are best avoided.

Azithromycin, a widely used antibiotic for common infections, a new study has found to be deadly for adults with heart problems or are at risk for it. Azithromycin or Zithromax is prescribed for all types of bacterial infections from ear infections, bronchitis, pneumonia to sore throat. Though more expensive than other antibiotics, it is popular because it often can be taken for fewer days.

The study, published in the New England Journal of Medicine, found that its use may increase their likelihood of sudden death, by possibly causing abnormal, potentially fatal heart rhythms. They found a 2.5 per cent greater risk of death from heart disease in the first five days of using Azithromycin other than using other antibiotics or no antibiotic at all.

In addition, the study indicated this antibiotic should also not be used in people with diabetes or a previous heart attack, and those who have undergone bypass surgery or have had stents implanted because it may has similar effects on them as well.

The researchers analysed health records and data on millions of prescriptions for several antibiotics given to about 540,000 Tennessee Medicaid patients from 1992 to 2006. There were 29 heart-related deaths among those who took Azithromycin during five days of treatment.

To compare risks, the researchers calculated that the number of deaths per one million courses of antibiotics would be about 85 among Azithromycin patients versus 32 among amoxicillin patients and 30 among those on no antibiotics. Of course, the patients in each group started out with comparable risks for heart trouble.

Patients studied were age 50 on average and not hospitalised. Most had common ailments, including sinus infections and bronchitis. Those on Azithromycin were about as healthy as those on other antibiotics, making it unlikely that an underlying condition might explain the increased death risk.

They found that the risk of death while taking the drug was more than double that of patients on another antibiotic, amoxicillin, or those who took none. Also, the highest risks were in Azithromycin patients with existing heart problems.

Zithromax, marketed by Pfizer Inc., has been available for decades. The researchers decided to study the drug’s risks because of evidence linking it with potential heart rhythm problems. Also, antibiotics in the same class as Zithromax have been linked with sudden cardiac death.

Mrs Helen Oduntan, Chairperson, Association of Lady Pharmacists, Oyo State, who agreed with the finding, stated that it was better people be more cautious on the use of any medication, including antibiotics.

Much as people already taking Azithromycin would not be asked to stop its use without first consulting with their physicians, Mrs Oduntan assured that FDA has commenced investigating into the possibility of Azithromycin disrupting heart rhythms.

According to her “with such an information that Azithromycin may increase chances of sudden deadly heart problems, it is better that people especially with heart problems, or those predisposed to heart problem such as the diabetics, avoid the use of this antibiotic.”

But Pfizer issued a statement saying it would thoroughly review the study. “Patient safety is of the utmost importance to Pfizer and we continuously monitor the safety and efficacy of our products to ensure that the benefits and risks are accurately described,” the company said.

Experts say that doctors and patients need to know about the potential risks as the results also raise concerns about long-term use of Zithromax, which other research suggests could benefit people with severe lung disease.

Similarly, they stated that the study provided another reason to curb overuse of antibiotics, which are too often prescribed for colds and other viral infections that they cannot treat. The overuse has contributed to the emergence of dangerous, drug-resistant strains of bacteria.

Additional research is needed to determine if its use could be dangerous especially as another research suggested that Azithromycin could benefit people with severe lung disease.

Likewise, a study provided another reason to curb the abuse of tetracycline, another common antibiotics often given to fight bacterial infections such as in the urinary tract and intestines, as well as severe acne and rosacea. It is also used in the treatment of chlamydia.

Researchers reported that male pseudoscorpions, a small scorpion-like arachnid, treated with the antibiotic tetracycline suffer significantly reduced sperm viability and pass this toxic effect on to their untreated sons.

Researchers at the University of Nevada, Reno reported in journal, Nature, that tetracycline could have a significant detrimental effect on male reproductive function and sperm viability.

In the current study, tetracycline was found to reduce sperm viability by up to 25 per cent. Unfortunately, this toxic effect is passed on to the next generation.

This first research to show a transgenerational effect of antibiotics involved a three-generation study of the pseudoscorpion and the researchers believe the same effect could occur in humans and other species.

To control for genetic influences, in the first generation, brothers and sisters from each of 21 broods were either treated with weekly doses of tetracycline from birth to adulthood or were reared as untreated controls. Subsequent generations were not treated with tetracycline.

They found that the antibiotic had no effect on male or female body size, sperm number or female reproduction.

But Mrs Oduntan stated that animals studies cannot be correctly extrapolated to what happens in humans, adding that the finding that tetracycline could affect sperm virility needs to be taken with a lot of caution.

Mrs Oduntan, who stated that animal studies may help to ascertain the effect of drugs, including their toxicity, declared that in some instances, drugs found to be safe in animals could turn out to be toxic in humans and as such animal study findings cannot be extrapolated directly to humans.