How Heat Affects Medications

Every year, the Spanish Agency of Medicines and Medical Devices (AEMPS) publishes a document on safety in the event of a heat wave. It contains information on the proper use of medications and how to preserve them.
How Heat Affects Medications

Last update: 05 June, 2021

You’ve probably witnessed how heat affects medications. High summer temperatures are a factor to take into account due to their possible influence on medication stability.

Every year, the Spanish Agency of Medicines and Medical Devices (AEMPS) publishes a document on safety in the event of a heatwave. It contains information on the proper use of medications and how to preserve them. It also contains specific heatwave recommendations for patients with particular medical conditions.

How to store medications in hot weather

In the case of high temperatures, medicines to be stored between 35 and 46 °F should be consumed as soon as they’ve been taken out of the refrigerator. On the other hand, drugs that must be stored at temperatures below 77 or 86°F usually tolerate more heat.

You must take conservation precautions into account when transporting your medications, even resorting to a portable refrigerator if necessary. In any case, drugs, in general, shouldn’t be exposed to high temperatures for long periods of time. Some people even leave them in the trunks of their cars, exposed to the sun!

If you have to take any drug, it’s a good idea to read the medication package insert carefully and consult your pharmacist if you have any questions or see warnings that you don’t understand or are worried about. Since some drugs require refrigeration, experts recommend keeping them out of environments hotter than 77 to 86°F.

A pharmacist at the pharmacy.
You should read the medication package insert to discover what its ideal storage temperature is.

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How heat affects medications

Some pharmaceutical forms, such as suppositories, ovules, or creams, are quite sensitive to high temperatures. In this case, the active principle isn’t sensitive to heat but the pharmaceutical form itself. Therefore, you should evaluate different aspects to know exactly how heat affects medicines. Some of them are:

  • Pharmaceutical form. Specific pharmaceutical forms, such as suppositories, ovules, or creams, are quite sensitive to temperature spikes. In this case, it’s pretty easy to see if they’re in good condition after exposure to heat.
  • Appearance. Keep a close eye on the appearance of the box, the presentation, and the drug. You need to make sure that both the packaging and the product itself are in good condition. The consumer is the one who determines the drug’s stability after analyzing its external appearance. When in doubt, it’s best not to take it.

Thermolabile drugs

The conservation of thermolabile drugs, especially those that have to be stored between 35 and 46 °F, is important during a trip. Using refrigerated isothermal packaging for these drugs is essential.

Heat can affect the drug, especially if it’s exposed to high temperatures for a long period of time. This may alter its effect and could lead to adverse effects. In the case of high temperatures, experts recommend taking these types of drugs as soon as you take them out of the refrigerator.

Some drugs in the fridge.
Some drugs can only be stored in refrigerators to maintain their integrity.

Some AEMPS recommendations

The Spanish Agency of Medicines and Medical Devices established some guidelines for the proper use of medicines in high temperatures. These include the following:

  • Don’t reduce or interrupt treatments without consulting your doctor.
  • Avoid taking non-steroidal anti-inflammatory drugs (NSAIDs) as much as possible, especially nephrotoxic drugs, when there’s a risk of dehydration.
  • Don’t take acetaminophen in case of heat illness, as experts have proven its ineffectiveness in treating it.
  • If your doctor prescribed you a diuretic drug, keep in mind that they’ll have to readjust your fluid and sodium intake.
  • Don’t take any drugs before consulting your doctor, as they can interact with other treatments or cause unwanted effects.

Conclusion

Throughout the year, and especially at times when the temperatures are very high, you should store drugs in cool and dry places, not directly exposed to sunlight. If you have any doubts, you should read the package insert of the drugs you buy, as it contains important storage information.

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