How to Store Phentermine

A Comprehensive Guide to Storing Phentermine.

This article is for informational purposes only and should not be used as a substitute for professional medical advice. Always consult your healthcare provider before starting any new medication or supplement regimen.

Proper storage of phentermine is crucial to maintain its effectiveness and ensure safety. It should be kept at room temperature, away from direct sunlight and moisture, and out of reach of children, while expired or improperly stored medication should be disposed of properly.

How to Store Phentermine

Too busy for the full read? Here’s what you need to know:

  • Phentermine is a prescription medication used to aid weight loss and should be stored properly to maintain its effectiveness.
  • It should be stored at room temperature, away from direct sunlight and moisture, and kept out of reach of children.
  • The medication should not be stored in the refrigerator or exposed to extreme temperatures, as it can affect its efficacy.
  • Phentermine tablets or capsules should be swallowed whole with a full glass of water and should not be crushed or chewed
  • Expired or improperly stored phentermine should be disposed of properly, preferably through a medicine take-back program.
  • The article also provides insights into the science behind phentermine, its use, and the importance of proper storage and handling.

Understanding Phentermine

Phentermine is a prescription medication classified as a sympathomimetic amine, which works by stimulating the central nervous system to suppress appetite ( 1 ). It is typically prescribed on a short-term basis, in conjunction with lifestyle changes, to help manage obesity.

Proper Storage of Phentermine

The way medications are stored can significantly impact their effectiveness and safety.

Phentermine, like many other medications, should be stored under specific conditions to maintain its potency and prevent degradation ( 2 ).

Room Temperature Storage

Phentermine should be stored at room temperature, typically defined as between 20 and 25 degrees Celsius (68 to 77 degrees Fahrenheit).

This range provides an optimal environment that helps maintain the medication’s efficacy. It’s important to note that room temperature can vary depending on the climate and the specific conditions of the room.

Therefore, keeping the medication in a place where the temperature remains relatively stable is crucial.

Safe Storage Practices

In addition to the proper temperature, certain safe storage practices should be followed:

  • Keep phentermine out of reach of children to prevent accidental ingestion.
  • Store away from moisture and humidity, like in bathrooms or kitchens. Humidity can break down the medication.
  • Avoid storing in direct sunlight, which can also degrade phentermine over time.

Handling Phentermine

It is important to use phentermine only as prescribed and not exceed the recommended dosage to avoid serious health risks.

The medication should not be crushed or chewed, as this can release all of the drug at once, increasing the risk of side effects ( 3 ).

Phentermine is typically taken once daily before breakfast or 1-2 hours after breakfast and should be avoided in the evening due to potential insomnia.

Disposal of Unused or Expired Phentermine

Unused or expired phentermine should be disposed of through a take-back program, not flushed or poured down the drain unless explicitly instructed. Pharmacists or local waste management authorities can provide safe disposal instructions.

In summary, phentermine storage, handling, and disposal are essential to maintaining its efficacy and ensuring patient safety. Always consult with your healthcare provider or pharmacist if you have any questions or concerns about your medication.


What is the best way to store phentermine at home?

The best storage for phentermine is at a controlled room temperature between 68-77°F (20-25°C). Keep it in a secure, dry location out of direct sunlight and away from heat sources. Store phentermine in a locked cabinet out of reach and sight of children and pets.

Can phentermine be stored in the refrigerator?

No, do not store phentermine in the refrigerator. Cold temperatures can negatively impact the medication’s effectiveness. Always keep phentermine at room temperature.

What should I do if my phentermine tablets have been exposed to heat or moisture?

If your phentermine tablets have been exposed to excessive heat or moisture, they may have degraded. Do not take the medication. Safely dispose of the tablets through a take-back program and contact your doctor for a new prescription.

How long can I store phentermine before it expires?

Check the expiration date printed on your phentermine prescription label or packaging. Do not take phentermine after expiration, as it may have lost potency. If unsure, contact your pharmacist.

What should I do with expired phentermine tablets?

Never flush expired medications or throw them in the trash. Find a prescription drug take-back program to dispose of unused phentermine safely. Some pharmacies also collect unused medications.

Can I take phentermine if it has been stored improperly?

Do not take phentermine that has been stored improperly, as it may be less effective or potentially unsafe. Contact your doctor or pharmacist before taking medication that you suspect was not stored correctly.

How should I handle phentermine tablets or capsules?

Always follow your doctor’s instructions for taking phentermine. Swallow tablets or capsules whole with a full glass of water. Do not chew, crush, split, or dissolve phentermine before swallowing unless instructed to do so.

What precautions should I take when storing phentermine?

Store phentermine in its original prescription container at room temperature and keep it secure, dry, and out of direct sunlight. Always keep it out of sight and out of reach of children and pets.

Can phentermine be harmful if not stored correctly?

Yes, improper storage can make phentermine less effective or potentially unsafe to take. Extreme heat and moisture can affect the medication.

What are the risks of not properly storing phentermine?

Improperly stored phentermine may lose potency and efficacy. It also poses safety risks if accidentally ingested by someone other than the patient, especially children.

  1. (2023) Phentermine Prescribing Information 
  2. Mayo Clinic Phentermine (Oral Route)
  3. MedlinePlus Phentermine