What are the Signs of a Diphenhydramine Overdose?

Diphenhydramine is a type of medication known as an antihistamine. This type of medication is typically used to treat allergic reactions such as hives and itching. If a person takes more than the recommended amounts of this medication, it could cause a potentially fatal diphenhydramine overdose. Some of the symptoms that may indicate the possibility of a diphenhydramine overdose include weakness, seizures, or hallucinations. A suspected diphenhydramine overdose should be considered a medical emergency.

Early signs of a diphenhydramine overdose may include nausea, stomach pain, and dry mouth. The patient may also experience an inability to sweat or urinate. The affected person may appear to be unsteady or may have difficulty making normal body movements. Rapid heartbeat, extreme drowsiness, and skin flushing may also be present. Even if the symptoms seem mild, it is important to seek immediate medical attention in order to prevent the possibility of developing severe complications.

Neurological indications of a diphenhydramine overdose may include confusion or agitation. The patient may also appear incoherent and may not be able to focus or comprehend well enough to hold even a simple conversation. More disturbing signs may involve the presence of hallucinations or delirium. The caregiver may need help getting the patient to the nearest hospital if these symptoms are present. It may be wise to call emergency medical personnel to transport the patient to the hospital.

Whenever possible, the caregiver should try to gather some information that will be helpful to the medical staff. Emergency personnel will likely ask how much of the medication was taken and the time it was ingested. It is helpful to know the general weight of the patient, the patient's age, and the overall health of the patient. This information is not absolutely necessary, and attempting to obtain this information should not prevent the caregiver from calling for medical help immediately.

Treatment for the diphenhydramine overdose will begin as soon as the patient arrives at the hospital. Activated charcoal may be given in an effort to absorb some of the medication from the body. A small tube known as an IV may be placed in a vein so that medications can be quickly delivered directly into the bloodstream. In some cases, the stomach may be pumped or oxygen therapy may be needed. With proper medical care, a diphenhydramine overdose is rarely fatal, and a complete recovery generally takes only a day or two.