Benadryl And High Blood Pressure Association

The relationship between Benadryl and high blood pressure arises from the effect the medication has on blood vessels and also its interaction with hypertension medications.

Benadryl is an antihistamine which is used, among other things, to treat allergy symptoms such as itching and watery eyes, skin rush and running nose. It is also a popular drug to treat colds and is used by millions of people during the cold season to clear stuffy nose.

It is important to keep in mind that Benadryl is a brand name. The active ingredient found in the drug that has a possible effect on blood pressure is diphenhydramine. What this means is that drugs with diphenhydramine can affect blood pressure.

Benadryl is a decongestant which works by constricting blood vessels. If you know anything about high blood pressure or hypertension, you would appreciate that blood vessel constriction causes elevated blood pressure.

While the drug is intended to constrict blood vessels in the nose and sinuses, unfortunately it constricts blood vessels all around the body.

When the vessels are constricted the heart works harder to push blood through the constricted vessels which results in increased blood pressure. This increases the risk of damage to important organs such as the heart and kidneys.

To reduce the risk of constricting the entire network of veins in your body resulting in elevated blood pressure, some pharmaceutical drug manufacturers recommend using spray based nasal decongestants. This helps localize the constriction of the blood vessels to the nose vs orally taking syrup, tablets, or capsules which would have the effect of constricting the flow of blood around the whole body.

Looked at from this perspective, orally administered Benadryl has potential to cause serious problems in individuals suffering from high blood pressure. It is for this reason that the drug is not to be used by individuals suffering from "severe high blood pressure, severe heart blood vessel disease, rapid heartbeat, or severe heart problems" according to pharmaceutical information on the drug.

Benadryl and High Blood Pressure Medications

The relationship between Benadryl and high blood pressure also emanates from the potential of Benadryl to interact with blood pressure medications. For example, Benadryl may interact with Betablockers which are drugs used to slow down the heart rate in order to reduce high blood pressure.

Betablockers are also used to treat certain heart conditions. Diphenhydramine or Benadryl, as it is better known, may affect how well other medications work or how well Benadryl itself works.

Possible Benadryl Side Effects

The following are some known Benadryl side effects. Keep in mind that the actual side effects will differ from person to person. Some individuals may as well suffer certain side effects which are not necessarily listed here. Whether the side effects are mild or severe will depend on the dosage taken and other factors that may or maybe unknown.

1.     Constipation
2.     Dry mouth
3.     Drowsiness
4.     Dizziness
5.     Excitation (especially in children)
6.     Nausea
7.     Nervousness
8.     Thickening of mucus
9.     Blurred vision or any change in vision
10.     Confusion
11.     Difficult or painful urination

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