Brief Answer:
Shelf life is around 2 years while effectivity in the body is around 36 hrs

Detailed Answer:
Hi! Welcome to Healthcaremagic. Thanks for sharing your concerns with us. We will try to help you in best way possible.

Based on the history you have shared, shelf life is around 2 years but depends on storage conditions and humdity as well as direct sun light exposure etc.

In ideal conditions it is around 2 years but all such drugs should be stored in comparatively cooler envoirnment than room temperature but dry and dark places preferably.

Once taken, the effectiveness of drug dose is determined by half life of the drug which is the amount it stays in the system at therapeutic levels before getting excreted or degraded by enzymes inside the body and in this case it is around 6 hours to 36 hours for one dose but if continously taken in doses the therapeutic levels may tend to remain for few days even after stopping.

Hope this has answered your query. If you have any questions please feel free to ask.

Regards

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