Could an expired drug still be effective?

Question

I was given an anti flu vaccine last Feb 3, 2007 i noticed the expiry was last January 2007. I discuss it to the medical personnel and he said that there is a 3 month grace period for this vaccine. Is it true and will this cause no adverse effect on my body?

Answer 1

From a health standpoint, it's not going to hurt you. The expiration date is a date beyond which the manufacturer cannot guarantee 100% effectiveness. And when the expiration date says January 2007, it means the last day of January 2007. So you only went over the expiration date by three days. This likely doesn't matter a hill of beans.

From a legal standpoint, what the medical person says is false. Expired drugs and vaccines are considered adulterated for the purposes of the federal Food Drug and Cosmetic Act. Giving you an expired vaccine was illegal. (They probably did it so they could save money and not have to throw out the expired vaccine.) You deserve better than that. At least, you should expect a refund. You could also complain to the FDA or the state board of medicine about this practice.

Answer 2

The date on most drugs/vaccines is the last date on which they can guarantee 100% efficacy. After that, you see a parabolic decline in effectiveness, but many of these, depending on your particular haptotype, continue to elicit sufficient response to provide full coverage. Most drugs/immunizations try to force a response by a biological system, and studies I did in graduate school show that certain bioactive substances are effective down to parts per billion, meaning that you really don't need much at all to start the chain reaction inside your body that the drugs intend for.

Oftentimes, the dosage is high to ensure long term effect. Some reactions have an event horizon, meaning that it must reach a certain level to elicit ANY response at all. However, most immunological responses depend on your macrophages and not on the amount of antigen present to elicit a response, meaning that antigen turnover and signal strength for T-cells and B-cells dictate response. All other drugs depend on enzyme-substrate interaction strength, and so drugs typically overdose in order to outcompete inhibitors or ensure sufficient concentrations at the intended target site to find the target enzyme before other enzymes recycle the drugs into things your body might actually need.

Answer 3

It probably is true.

The drug company can sell more vaccine if you follow the printed date.

It's about the money.

Any vaccine may not work at all, even within acceptable dates. You MUST get what is called a titer --a test that the vaccine is actually causing your body to produce the desired antibodies.

You must wait a certain amount of time for the titer to be accurate.

Answer 4

the date on the package always provides a safe window or cushion to the manufacturers liability risk. some things can theoretically last longer than we or our societies will last, but they're never labeled more than a few years after production at most. Negative effects of things that have spoiled or degraded can vary from just being useless to being harmful depending on the product.

Answer 5

its probably fine. my boyfriend went to the doctor for migranes and was given a ton of expired migrane medication for free. the doctor said they would be fine for a couple months. so yeah i believe the 3 month grace period. after all, drug companies have to cover their butts everywhere. drug lawsuits are usually the big lawsuits

Answer 6

Expired drugs are usually not dangerous but they may lose their effectiveness. However, a month or two past expiration date should not be a problem. I would not worry about it.

Answer 7

don't take any expired anti-biotics or you will most likely get very very sick ask a doctor before you take it don't listen to any one on here different medicines are different when ther expired..i have an asthma medicine that jusst gets weeker when it's expired but i've got a medicine for when i had a head injury that can kill you if it's expired

Answer 8

I would not use it.There is a reason why they have expiry dates.