Hyderabad: Do medicines lose their potency as the expiry date nears? Are they safe? Or is it a marketing gimmick by pharmaceutical companies?
There is no specific scientific report on existing drugs that states that potency reduces over a period of time.
A senior pharmaceutical company official says that the expiry date was designed “to ensure that every drug has the specific potent chemicals and is safe for consumption. To ensure that only the batch of drugs that are required for people are out in the market. But in India, it is more about selling the numbers and making profits. Expiry date does not indicate a point when a medication spontaneously or suddenly loses potency. It does not even mean that after that date the medicine is toxic.”
There have been instances when batches of seized drugs tested in a government laboratory have been found to be of sub-standard quality. But this is because there is deficiency in the potency of the drug from the time of manufacture.
A senior state government drug controller explains that when the potency of a drug reduces from the time it was manufactured, then it means the drug is decaying.
“The chemicals are of highly sub-standard quality and they are beginning to wear off even before the expiry date. In these cases there is no guarantee that the drugs will be safe till the expiry date,” says the senior state government drug controller.
In many medicines factors like storage, transportation, temperature and packaging play a major role. If these are not maintained as stipulated, the drugs could be less efficacious. That is why no guarantee is given by any manufacturer about the safety and efficacy of drugs even till the expiry date.
Anti-epileptic drugs such as vigabartin, gabapentin, lamotrigine, topiramate, tiagabine, and levetricacetum, and anti-angina drugs such as nitroglycerine have shown adverse results in a few patients when taken after the expiry date.
Documented harm has been found in the case of tetracycline, oral contraceptives, eye drops and insulin where it has led to near fatal situations.
Pharmacist Dr Sai Kumar Katam says we need more scientific evidence about expired drugs, whether they are really toxic and harmful. “The argument put forth by the industry is that medicines are safe to use before expiry date and that is the reason the manufacturer guarantees its full potency and safety.”
weather plays spoilsport with potency
Medicines can lose potency even before the expiry date due to unsuitable climate conditions such as extreme heat, dryness or humidity. This can alter the chemical combinations.
“Medicines are prone to bacterial, fungal and other contaminants if they are not manufactured properly or if they are damaged during transportation. This means that this particular category of medicines is not fit for consumption,” a medical expert said.
There have also been medicines which have been kept safely for a year after the expiry and they are found to work.
This is because the manufacturer is labelling an expiry date after checking on the stability of the drug. This particular process is approved by United States Food and Drug Administration. These guidelines are followed by all pharmaceutical companies in India. For this reason, the stress is on proper storage at the retail centres so that drugs are stable and do not lose their potency before the expiry date.
