Drug InteractionThere is no known drug interaction between Celebrex and Benadryl. They are considered safe to take together. In addition, they don't share many similar side effects so taking both together generally doesn't increase the risk of additive adverse reactions.

What Is Benadryl?

Benadryl (diphenhyramine) is used to treat allergy symptoms and short-term insomnia. It works as an antihistamine, by blocking the binding of histamine to receptors in the body.

Sedation is the most common side effect seen with Benadryl, which has led patients to use Benadryl as a sleep aid. The sedation seen in patients is why its use is not recommended in those patients 65 years of age or older. Elderly patients are more sensitive to the effects of Benadryl and are more susceptible to falling and sustaining injuries under its influence.

Other side effects of Benadryl include:

  • Constipation
  • Urinary retention
  • Blurred vision

What Is Celebrex?

Celebrex is a NSAID (non-steroidal anti-inflammatory drug) that is typically used to treat mild pain and inflammation. This medication is different from the other NSAID agents because Celebrex is more selective for the inflammatory COX-2 enzyme, which means that it is less likely to cause gastrointestinal bleeding and ulcers.

Even though it has a lower risk of causing a peptic ulcer, the patient there is still a risk of exacerbating cardiovascular disease. Therefore, Celebrex should not be used in most patients who have cardiovascular disease, although there are exceptions. Celebrex is cleared through the kidneys, so its use is not recommended in patients who have severe renal impairment as it can cause more damage to the kidneys, and it can accumulate in the body, increasing the risk of side effects.