Why Drugs Are Temperature-Sensitive

Changes can affect medication stability

Active drugs used in medications are temperature-sensitive. When stored in hot or cold places, they can become unstable and even degrade, posing a risk of negative side effects and decreasing their effectiveness.

Drug companies are required to strictly control temperatures during manufacturing. And most medications must be stored at a controlled room temperature of around 68 to 77 degrees F once you get them.

This article covers how to protect your medications from a variety of elements and what to do if they are exposed to potentially harmful temperatures.

Temperature-Sensitive Medications

Few medications remain stable in warmer climates of 93 degrees or higher. Temperatures in many parts of the world can surpass this, depending on the season.

If you are traveling or moving someplace hot, you will need to find ways to keep your medication cool.

Most antibiotics are temperature-sensitive. According to one review, only three antibiotics have shown stability in warmer climates:

  • Benzylpenicillin, an antibiotic used to treat streptococcal infections (strep)
  • Cefoxitin, an antibiotic used to treat pneumonia and other respiratory infections
  • Flucloxacillin, an antibiotic used to treat skin, ear, and other infections

On occasion, a medication may need to leave its recommended temperature range, for example, while being shipped. This is known as a permitted excursion. Depending on the medication, this may be permitted when necessary, but only for a short and specific period of time.

Temperatures for Medication Storage

Storage recommendations and any excursion information should be labeled on the drug product's packaging or information sheet.

Examples of temperature-sensitive drug recommendations include:

  • Lipitor (atorvastatin calcium) for treatment of high cholesterol: Room temperature
  • Toprol (metoprolol succinate) for treatment of hypertension and heart failure: Room temperature; between 59 and 86 degrees F for excursions, if needed
  • Norvasc (amlodipine besylate) for treatment of high blood pressure: Room temperature
  • Synthroid (levothyroxine) for treatment of hypothyroidism: Room temperature; between 59 and 86 degrees F for excursions, if needed
  • Veletri (epoprostenol) to treat pulmonary hypertension: Between 35.6 and 46.4 degrees F

Compounding Pharmacies

If you are getting your medication from a compounding pharmacy, your healthcare provider has prescribed you a specific formulation that is not readily available.

These medications are prepared individually for each person, not in high volume like most commercial drugs.

Pharmacists must follow strict protocols. Often, especially with liquid or injectable compounds, these formulations require highly-controlled storage and transport temperatures. Otherwise, they may not last as long as most medications.

Risk Factors for Temperature-Sensitive Drugs

There are a number of factors that can expose your medications to dangerously high temperatures.

  • Hot weather: If you don't have air conditioning (and keep it on 24/7 during hot spells), high outside temperatures can cause your home to become warm enough that medications "overheat." This is a particular concern during power outages.
  • Car: Storing your medicine in your car for an extended period of time can expose it to high heat.
  • Travel: Your medication may sit in your luggage on a hot tarmac or in non-air conditioned luggage handling areas.
  • Pharmacy: If your pharmacy loses power for an extended period of time before you picked up your prescription, you may be unaware of the problem.
  • Delivery: If you get your medicines from a mail-order pharmacy, they could be delivered in a non-temperature regulated truck or may sit in your mailbox for an extended period of time.

How to Protect Your Medication

how to protect your medication
Illustration by Emily Roberts, Verywell 

You can take some steps to prevent heat-related degradation of your medications.

  • Check the storage information for any medications you take so that you are aware of the temperature recommendations.
  • Carry medications on the airplane with you, instead of storing them in your checked luggage. Your security and customs check-in will be more efficient if you travel with your medicines in their original containers with pharmacy labels.
  • Do not store medications in your car or trunk for extended periods. Take them with you when you leave your car.
  • Ask your pharmacy if they have an emergency generator to maintain temperature control for refrigerated medications.
  • Request that mail order prescriptions come in temperature-controlled packages if you have the option. Use overnight delivery methods and be there to accept packages.

What to Do If Your Medication Has Been Exposed to Excessive Heat

If your medication has already been exposed to high temperatures, talk to your pharmacist to see if you need to replace it.

Your next step should be a call to your health insurance company or HMO, who may be able to replace your medication at no cost or reimburse you for a replacement prescription.

Finally, if your pharmacy and insurance company are unable to help you, contact the manufacturer through the consumer hotline. Many manufacturers will allow you to return the medication in exchange for a replacement.


Active chemicals in most OTC and prescription medications react strongly to high temperatures. Exposure to high temperatures for too long can cause a medication to degrade and become ineffective or even harmful. If your medication has been exposed to a high temperature, contact your pharmacist or healthcare provider before using it.

A Word From Verywell

Medications should always be kept in a cool, dry place. If you find yourself in a situation where you simply cannot manage to keep your medication cool and dry, you'll need to make accommodations. For traveling, spending a day outdoors, or any other warm occasion, consider bringing an insulated cooler bag with you to carry your medication. Add a few ice packs to keep the bag cool, making sure that your medication also stays dry.

1 Source
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. John Perks S, Lanskey C, Robinson N, Pain T, Franklin R. Systematic review of stability data pertaining to selected antibiotics used for extended infusions in outpatient parenteral antimicrobial therapy (OPAT) at standard room temperature and in warmer climates. Eur J Hosp Pharm. 2020 Mar;27(2):65-72. doi:10.1136/ejhpharm-2019-001875

Additional Reading

By Mary Shomon
Mary Shomon is a writer and hormonal health and thyroid advocate. She is the author of "The Thyroid Diet Revolution."