Expired medicines are a common and unpleasant reality of life in today’s developed world, and even in many relatively developed parts of low- and middle-income countries. Once a medication has passed its expiry date, it is not expected to be used or sold.
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The reason for this prohibition is the potential loss of efficacy or the change in the chemical composition of the medication, which could pose a threat to health. In some cases, bacteria may grow in the medication.
Weakened antimicrobial products may promote bacterial resistance by treating infections incompletely, allowing resistant organisms to survive and proliferate. This in turn may lead to the spread of more serious infections.
For these reasons, the US Centers for Disease Control and Prevention (CDC) recommend that expired medicines not be used but discarded instead. However, this is regarded with a quizzical eye by many other experts, for several reasons.
The expiry date is simply “the final day on which the manufacturer of the medication guarantees fully its quality and safety.” This is determined by testing the stability of various ingredients.
What happens beyond this date? Medicine does not automatically become ineffective once the expiry date is passed. However, the degree of certainty accompanying its chemical composition is reduced. This is the fundamental issue with such drugs – not knowing how the chemical composition has been altered, and hence ignorance of the resulting potential for reduced quality and safety after this date.
The exposure of the drug to light, heat, and mechanical trauma plays a large role in the stability of the drug after the expiry date. The drug thus passes into the realm of the unknown. This area thus requires intensive investigation to avoid unnecessary wastage and maximize the efficiency of drug use.
Extending the shelf life
In fact, the US Army added anywhere between 5-20 years to the period of efficacy to most sampled drugs in its stores, via the Shelf Life Extension Program (SLEP), after finding that millions of dollars worth of expired medicines were due to be destroyed.
It examined drugs like tetracycline, finding that two years or more from expiry, there were no signs of toxicity. Other drugs like diclofenac have been alleged to form toxic products on exposure to light, and these need to be verified.
Earlier conclusions that expired medicines can cause kidney damage in humans must be questioned, with the many changes that have occurred in the manufacturing cycle since then.
In another study of drugs at up to 40 years from their expiry date, but still in their original packing and unopened, the researchers established that 90% or more of the original drug activity remained in 12/14 medicines. The fall in efficacy, albeit small, must be taken into account when setting the expiry date, as must the difference between tropical and temperate conditions.
It would be necessary to look at the findings of the US military in their research on drug shelf life in tropical Africa to extrapolate their conclusions to other tropical regions. Differences in manufacturing conditions and batch must also be considered when extending the shelf life, say some scientists.
The World Health Organization (WHO) created lists of medicines classified by their ‘need’ grade. One such list, of indispensable medications, was supposed to form part of a national survival resource. Specific medications were also placed in a depository for use in emergencies.
Many LMICs suffer from a shortage of pharmaceuticals, such as antibiotics. Medical ethics may demand the consideration of whether expired medications should be shipped to such countries to prevent them from being unnecessarily destroyed while supplying a part of the shortage in this setting.
In keeping with this goal, the donation of expired but usable medications to developing countries seems to be a step forward. Unfortunately, the WHO itself recommended in 1999 that expired or unused pharmaceuticals should not be reused.
This ignores the sum of evidence that the expiry date is not actually the date on which the medication loses its efficacy. This points to the need to set up programs that officially extend the shelf life of drugs so that they can be used in developing countries beyond their expiry date. This would enhance healthcare and thus prolong the healthcare and life span of the residents.
However, a comprehensive and detailed assessment of the local factors, including climate, environment, and culture, must be carried out before such an extension can be officially made.
Proper disposal
How should old and expired medicines be cleared out? For one, dumping them down the toilet or into the waste is a potentially dangerous practice that should be stopped, because it contaminates the environment, including water bodies, with hormones and antibiotics, among other powerful drugs, that can cause profound metabolic and physiological changes in living organisms in their habitat.
Secondly, opioids and other dangerous drugs should be safely disposed of to prevent their falling into the wrong hands. Especially troubling is the high number of children who visit the emergency department each year because of unsupervised handling of such drugs, at over 50,000 a year.
Pets can also be severely harmed by expired medicines that have not been properly disposed of. But is just ‘wasting’ these medicines the answer?
When expired medicines are disposed of by private citizens, the most commonly used route is the garbage can or the toilet, in the absence of clear and well-known instructions from either the healthcare or legal side.
In many developed countries, a variety of drug return and disposal systems are freely available. One such is the drug take-back program (DTP), a local program that establishes itself with official or community help, and provides a safe disposal mechanism for drugs. This has not taken off properly in most countries.
Environmental contamination
Despite this, over three-quarters of participants in one study threw expired drugs into the garbage or toilet, while only one in seven returned them to the pharmacy. Interestingly, about 3% kept using these drugs after their expiry date was over.
When such rubbish is added to the landfill as such, the drugs will inevitably enter surface or ground waters. This has been demonstrated by researchers, such as those who tested the Grinsted landfill in Denmark, finding 13 organic chemicals from pharmaceuticals in groundwater from 23 points at various distances from the site.
Many countries incinerate their waste, but with such organic molecules, the firing requires high oxygen conditions, time, and temperatures to proceed. Conversely, burning at low temperatures may lead to the release of toxic substances. This could include aromatic toxins, heavy metals like selenium, molybdenum, and iron or zinc.
Ideally, the burning of pharmaceutical waste should be precisely controlled, otherwise, the remains from the burning sites still have the tendency to be discharged into the ecosystem where they may cause significant damage.”
Conclusion
It is undeniable that failures by the medical world, pharmaceutical companies, and legislators have led to the current lapse in responsible use and disposal of expired drugs. Pharmaceutical firms must think seriously about producing more drugs than are required based on current consumption patterns.
Secondly, developing new tests to evaluate the stability of the drug would help greatly to extend the expiry date where applicable, thus reducing the volume of drugs to be disposed of. Thirdly, all product packages should mention proper disposal instructions to raise the level of community awareness about this risk and its mitigation.
Secondly, DTP programs are required in many countries, and where available, they need to be made more popular and effective. These should be the first choice when it comes to expired medicines. The attention of the public should be attracted to this area by specific days or programs, for instance, enabling many people to learn and practice how to clear out unnecessary and outdated medications.
Federal guidelines in the USA state that in the absence of such guidelines, expired medicines may be disposed of in combination with other organic trash in a sealed container, thrown away with the household waste. Some medications should be disposed of into the toilet or sink because of the potential for consumption by children, pets, or others if ingested by accident after being thrown away in the manner described above.
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Further Reading
Deciphering the Mysteries of the Human Microbiome