If you take Benadryl every night what happens to your body is it can increase your risk for Alzheimer's disease and dementia and so ideally Benadryl should not be taken every night.
Benadryl is considered okay and safe for occasional use in most people but long term use of Benadryl is not considered safe as it increases your risk for dementia and Alzheimer's disease.
Benadryl is not recommended anymore because long term frequent use especially in adults 65 and older is associated with developing Alzheimer's disease and dementia because of their anticholenergic properties.
Also elderly people that take Benadryl and are hospitalized have an increased risk of delirium and other effects of Benadryl are dry mouth and low blood pressure when standing.
The FDA also warned that taking higher than recommended doses of the common over-the-counter (OTC) allergy medicine diphenhydramine (brand name Benadryl) can lead to serious heart problems, seizures, coma, or even death.
Despite the many misleading headlines, such as “Sudafed, Benadryl and most decongestants don't work,” the over-the-counter antihistamine Benadryl is not being pulled from pharmacy or store shelves.
Taking Benadryl long term might increase the risk of dementia, such as Alzheimer's disease, especially in older adults.
In one study , people over the age of 65 years who took medications such as Benadryl daily for 3 years or longer had an increased risk of dementia or Alzheimer's disease.
The side effects of Benadryl include.
Drowsiness.
Dizziness.
Impaired coordination.
Headache.
Epigastric discomfort.
Thickened bronchial secretions.
Dry mucous membranes.
CNS stimulation, paradoxical.