How Medicines in Creams, Ointments, Gels, Sprays, Lotions, and Patches Can Harm You

Republished November 15, 2024

Medicines that come in creams, ointments, gels, sprays, lotions, and patches enter your body by being absorbed through the skin. They can cause bad side effects if you use too much of the medicine. This can happen even if the medicine is only intended to treat a skin condition or numb the skin before or after a procedure.

Several years ago, two young women died after they applied a numbing gel to their legs after a laser hair removal procedure. The gel contained high doses of numbing medicines such as lidocaine and tetracaine. The gel was intended to help ease any pain associated with the procedure. The women were told to apply the gel to their legs after the procedure and cover their legs in plastic wrap. Both women had a fatal reaction to the gel because too much medicine entered their bodies through the skin.

These deadly reactions were caused by high doses of numbing medicine that was used to cover a very large area of skin (both legs). Also, using plastic wrap over the skin heated it, which caused nearby blood vessels to dilate and blood flow to increase. That, in turn, allowed more medicine than usual to be absorbed, which eventually was toxic to the body.

There are other medicines that can cause severe side effects if too much is applied to skin. This can even happen with over-the-counter (OTC) medicines. There have been reports of chemical burns from medicine patches such as Icy Hot (menthol, lidocaine) that were applied to the skin. In 2007, the death of a 17-year-old girl was blamed on the use of too much cream for muscle aches. She was a cross country runner and had been using the cream all over her legs to soothe aching muscles after exercise. Heat and exercise can increase the amount of medicine entering your body. Her body apparently absorbed high levels of methyl salicylate, an anti-inflammatory medicine related to aspirin that is found in sports creams. Used correctly, these creams can provide temporary relief from muscle pain but they shouldn’t be used for more than a week.

The cases described above are examples of harm that can occur when applying too much medicine on the skin. Even though harm does not happen often, medicines in creams, ointments, gels, sprays, lotions, and patches can enter your body just like medicines taken by mouth. When using these medicines, be sure to follow the directions and heed any warnings found on the Drug Facts label.

Here's what you can do: When using medicines that come in creams, ointments, gels, sprays, lotions, and patches, follow these recommendations:

1. Follow directions. Use the medicine exactly as stated on the label, or exactly as your doctor told you. Do not use more of the medicine than prescribed, and do not use it more often or longer than recommended.
2. Apply sparingly. Apply creams, ointments, gels, sprays, and lotions only on small areas as needed. Do not apply the medicine all over your body.
3. Avoid broken skin. Apply medicine patches only on areas of the skin where there are no cuts or sores.
4. Do not use heat or tight bandages. Do not apply a tight covering over the area where the cream, ointment, spray, gel, lotion, or patch has been applied unless told to do so by your doctor. Follow the instructions provided by the pharmacy for prescription medicine or those found on the Drug Facts label for OTC medicine. Tight bandages make the skin warmer, and heat increases the amount of medicine absorbed into the body. Do not apply heat (e.g., prolonged sunlight, hot tubs, heating pad, tanning beds) without checking with your doctor.
5. Seek medical supervision. Some cosmetic procedures may be performed without a medical doctor present (e.g., laser hair removal). Consider talking to a healthcare provider such as a doctor, pharmacist, or nurse about the creams or ointments you are instructed to apply to your skin.
6. Ask questions. Talk to a pharmacists when buying prescription or OTC creams, ointments, sprays, gels, lotions, or patches to make sure you use these products safely.

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