Lost The Cap To Descovy Bottle And Tablets Have Been Exposed To Air

In our latest question and answer, the pharmacist discusses the stability of Descovy tablets that have been left in the bottle without the cap.


I seem to have lost my cap to my Descovy medication container, so the medication has been exposed to air, but I have kept the container in a dark and dry place. I still have been taking the medication as prescribed but now I'm wondering if the medication has lost potency because it's been exposed to air. Should I be concerned that the drug has not been working? Should I finish the medication, or just get a new refill?

Asked by Jav On Dec 11, 2022

Answered by
Medical Content Reviewed By HelloPharmacist Staff

Published Dec 12, 2022
Last updated Jun 12, 2024

Key points

  • Descovy tablets are recommended to be stored at 77°F (excursions permitted to 59°F to 86°F) and in the original bottle, tightly closed, to protect the tablets from exposure to humidity.
  • Data from Gilead, the manufacturer of Descovy, has reported that Descovy tablets were stable for at least 28 days when stored in an open dish at 77°F and 60% relative humidity.
  • If you have lost the cap to your Descovy bottle, try to find a replacement cap or bottle to store your tablets to best protect them. If this isn't an option for you, be sure at the very least to store them at the recommended temperature and humidity levels to avoid premature degradation.
  • If you are at all concerned that your Descovy tablets have been stored improperly and in a way that could affect their stability, it is recommended to get a replacement.


Thanks so much for your question! While it's difficult to give an exact answer as to whether or not your Descovy tablets have been negatively affected by keeping them in an open bottle, I can certainly give you some information about the subject.

Descovy is recommended to be stored in the original bottle with the desiccant, and to be kept tightly closed to protect the tablets from moisture. If you've lost the cap to the bottle, the tablets certainly are more susceptible to being exposed to moisture from the air.

I will say that in all likelihood, the tablets will not have been negatively affected if they have been stored in the conditions you mention in your question (a dark, dry place at a recommended temperature). Descovy tablets don't lose potency simply by being exposed to air, it's certain conditions that can cause problems, like too high a temperature or humidity.

Additionally, data suggests that the integrity of the physical Descovy tablets will be affected by improper storage conditions before the actual drug would degrade or lose any sort of potency.

Descovy Stability Studies

Gilead, the manufacturer of Descovy, released some very helpful information regarding the stability of Descovy tablets in a variety of storage conditions (such as in the original sealed bottle, the original bottle without a seal, and an open petri dish).

I've included a picture of their data in the table below, but on the whole, it appears that if you have stored your Descovy tablets in a cool, dry, and dark place (lower than 77°F and 60% relative humidity), even if not in the original bottle, the tablets will be stable for at least 28 days.

In the table, Descovy is referred to by the abbreviations of the drugs contained in the product (FTC [Emtricitabine]; TAF [tenofovir alafenamide]).

Descovy Tablet Storage

The row that is fourth from the bottom seems to be the most applicable to your situation, and that is the data showing tablet stability for 28 days in an open petri dish at 77°F and 60% humidity.

The last two rows I didn't feel were applicable to you since those are for tablets in the original bottle with a cap, but the induction seal (the paper seal that covers the opening of the bottle) was removed.

The complete document from Gilead can be found below.

What To Do If You Lose The Descovy Bottle Cap

Descovy tablets are recommended to be kept in the original bottle, tightly sealed, to reduce exposure to the environment, specifically humidity.

If you've lost the cap, I recommend trying to find a replacement cap if you can. Likely places would be from a prior bottle of Descvoy you have or from your pharmacy.

Alternatively, you could move the tablets to another prescription vial/bottle, and store them that way. If you do this, be sure to keep the desiccant with the tablets.

If you cannot find a suitable replacement capsule or bottle, like the table I've included above shows, just be sure to store your Descovy tablets properly:

  • At 77°F (excursions permitted to 15°C to 30°C (59°F to 86°F)
  • At or below 60% relative humidity
  • Out of direct light

According to the data provided directly from the manufacturer of Descovy, as long as the tablets are stored under these conditions, they are stable for at least 28 days.

Final Words

As mentioned, in regard to exposing Descovy tablets to the environment, we are more concerned with tablet integrity versus the drug being degraded, although drug degradation may certainly happen over a longer period of time.

If you have noticed that your tablets appear to be degraded, I do highly recommend getting a new prescription from your pharmacy since, at that point, they may not be as effective. It's better to be safe than sorry!

Thanks for contacting us and please do so again anytime.


About the Pharmacist

Dr. Brian Staiger, PharmD

Dr. Brian has been practicing pharmacy for over 13 years and has wide-ranging experiences in many different areas of the profession. From retail, clinical, program development, and administrative responsibilities, he's your knowledgeable and go-to source for all your pharmacy and medication-related questions! Dr. Brian Staiger also has herbalist training and educational certificates in the field of medical ethnobotany. Feel free to send him an email at [email protected]! You can also connect with Dr. Brian Staiger on LinkedIn.

Recent Questions