Phentermine is a prescription medication used for weight loss. It is a stimulant that suppresses appetite and boosts energy. Many people wonder how long phentermine stays effective and can be safely used after the expiration date. Here is a look at the shelf life of phentermine and how long it typically remains potent.
Shelf Life of Phentermine
Like most medications, phentermine has a shelf life of around 2-5 years from the manufacturing date. The exact expiration date should be printed on the medication bottle or packaging. Phentermine, which is sold under brand names like Adipex-P and Lomaira, typically expires after about 3 years.
However, the expiration date is very conservative to guarantee effectiveness and safety. In reality, phentermine will usually remain good for 6 months to 1 year past the labeled expiration date if stored properly.
How to Store Phentermine
To get the longest shelf life out of phentermine, it is important to store it correctly:
- Keep phentermine in the original prescription bottle or blister pack.
- Store at room temperature away from excess heat, light, and moisture.
- Keep the medication bottle tightly closed.
- Do not store in humid places like the bathroom.
Storing phentermine properly will help the medication remain potent for as long as possible. Heat, humidity, and air exposure can accelerate degradation of the active ingredients.
How to Tell if Phentermine is Still Good
Here are some signs that phentermine may no longer be good beyond its expiration date:
- The color or texture has changed. Phentermine should be white or off-white.
- It has a stale smell or odor.
- The tablets are chipped, cracked, or melted together.
- It tastes bitter or unusual.
If phentermine shows any of these signs, it is best to stop using it and get a new prescription. Using degraded phentermine can potentially cause side effects or be unsafe.
Is Expired Phentermine Dangerous?
While expired medications are not recommended for use, phentermine is generally not dangerous if taken a little bit past its expiration date. However, there are some risks to be aware of:
- Reduced effectiveness – Outdated phentermine may not suppress appetite and boost energy as well.
- Unpleasant side effects – Degraded phentermine can sometimes cause headaches, nausea, dizziness, or other side effects.
- Toxic byproducts – Chemical changes in expired medications can produce potentially toxic compounds.
Using phentermine more than 6-12 months past expiration increases the chance of these risks. It is best to stick to phentermine within its labeled shelf life or only slightly past it.
Frequently Asked Questions
Can you take expired phentermine?
It is not recommended to take phentermine that is significantly expired. Phentermine will usually be safe to take up to 6-12 months past the expiration date, but effectiveness and safety declines after that. Check with your pharmacist or doctor before taking any expired medication.
Does phentermine expire?
Yes, phentermine does expire typically after 2-3 years from the manufacturing date. The exact expiration date should be printed on the prescription bottle or box. Properly stored phentermine can sometimes last 6-12 months past expiration.
Can expired pills make you sick?
Expired medications like phentermine can potentially make you sick if they contain degraded ingredients or toxic byproducts. Taking significantly expired pills increases the risk of side effects like nausea, dizziness, and headaches.
How long is phentermine good for after opening?
After opening, phentermine is usually good for the remainder of the expiration date if stored properly. Keep it in the original container, close it tightly, and store at room temperature to get the full shelf life after opening.
Can bad phentermine hurt you?
Phentermine that has degraded significantly past its expiration date can potentially be harmful. Using very outdated phentermine increases the risk of side effects and exposure to toxic compounds formed as the drug breaks down.
The Bottom Line
Phentermine typically expires after about 2-3 years. It will often remain safe and effective for 6-12 months past the labeled expiration date if stored correctly. However, it is best to discard phentermine after this buffer period has passed to avoid potential risks from degradation of the medication. Check your pills for any changes in appearance, smell, or taste, and if in doubt, get a new prescription from your doctor.
Always store phentermine in proper conditions and be mindful of the expiration date to get the full shelf life of this medication. Never take phentermine that is more than 12 months expired, as safety cannot be guaranteed at that point. With reasonable care and attention, phentermine can be used safely and effectively for weight loss even shortly after its expiration date.