Precautions and Warnings With Diphenhydramine
Specific Diphenhydramine Warnings and Precautions
Warnings and precautions to be aware of prior to taking diphenhydramine include the following:
- Elderly individuals may be more susceptible to the side effects of diphenhydramine (and may also be more likely to be taking medications that interact with diphenhydramine). If you are over the age of 60, it is best to check with your healthcare provider before taking diphenhydramine. Diphenhydramine can worsen many conditions common in the elderly (such as an enlarged prostate or Alzheimer's disease).
- Diphenhydramine is not approved to sedate children (such as for airline trips). Not only can this practice be dangerous, but it is often ineffective. In fact, diphenhydramine can have an opposite effect on children, sometimes making them hyperactive. Never use diphenhydramine for this purpose without the approval and instruction of your child's healthcare provider. Many healthcare providers advise against this practice.
- Diphenhydramine can cause blurred vision, dizziness, and drowsiness. Be sure to see how diphenhydramine affects you before driving or operating heavy machinery.
- Diphenhydramine can worsen stomach ulcers, GERD, glaucoma, or an enlarged prostate. If you have one of these conditions, do not take diphenhydramine without checking with your healthcare provider first.
- Diphenhydramine can cause breathing problems in people with asthma or COPD, including chronic bronchitis and emphysema. If you have asthma or COPD, check with your healthcare provider before taking diphenhydramine.
- Make sure to check with your healthcare provider before taking diphenhydramine if you have hyperthyroidism or any heart problems (including heart disease or high blood pressure), as it is possible that diphenhydramine could worsen these conditions.
- Never combine oral diphenhydramine products with diphenhydramine skin products. Also, do not use diphenhydramine skin products over a large area of the body. Either of these situations could lead to a diphenhydramine overdose.
- Diphenhydramine is considered a pregnancy Category B medication. This means that it probably will not cause problems if used during pregnancy, although the full risks are not currently known (see Diphenhydramine and Pregnancy).