Hemorrhoids are weakened, enlarged veins in the area of the anus. Sometimes they may bulge out, when they are most likely to cause discomfort or red blood on toilet paper. These swollen veins, also known as piles, are thought to be caused by excess pressure on rectal veins. Pregnant or overweight people and those who strain at stool might be most vulnerable to that kind of pressure. Although you might not imagine that hemorrhoid remedies would have any effects beyond the rectum, several readers have reported that Preparation H raised their blood pressure.
Preparation H Raised Blood Pressure Dramatically:
Q. I used Preparation H for some hemorrhoid irritation in the morning before I saw my doctor for a normal checkup. I almost broke the blood pressure machine. The nurse measured my BP three times because it was so high.
Of course, I tried to think what I had done that might raise my blood pressure so much. The next day I read the label on the Preparation H I was using and put two and two together. I do think the warning about increasing blood pressure should be clearer!
A. Preparation H contains the decongestant phenylephrine that constricts blood vessels. This action is how it shrinks swelling of hemorrhoidal tissues, as the ads used to say.
Phenylephrine when applied rectally has a short duration of action and has to be applied more than once a day for the effect to last longer. With multiple applications, the blood vessels remain constricted for a longer.
When you constrict blood vessels, blood pressure may rise. That’s why the label warns to “Ask a doctor before use if you have…high blood pressure.”
You are not the only one to have experienced this adverse effect.
Another reader wrote:
“I used Preparation H and had a sudden spike in blood pressure. My normal blood pressure reading is around 106 over 62.”
Doctor Doubted That Preparation H Raised Blood Pressure:
Q. After using Preparation H for several days, my blood pressure went to 206 over 98 and I ended up in the emergency department for hours.
Later that week I read in your column that someone else had experienced the same problem. My doctor was skeptical, to say the least, so I lent him the clipping. Now he can’t find it to return it.
Would you write about this again? I never had high blood pressure before in my life. It is always around 130 over 65.
A. Preparation H was reformulated many years ago, and now contains phenylephrine. This compound constricts blood vessels, which can cause an elevation in blood pressure.
There are warnings on the label:
“Ask a doctor before use if you have:
- heart disease
- high blood pressure
- thyroid disease
- diabetes
- difficulty in urination due to enlargement of the prostate gland
“Ask a doctor or pharmacist before use if you are presently taking a prescription drug for high blood pressure or depression.”
“When using this product do not exceed the recommended daily dosage unless directed by a doctor.”
The warning on the label used to say:
“Do not use this product if you have heart disease, high blood pressure, thyroid disease, diabetes, or difficulty in urination due to enlargement of the prostate gland unless directed by a doctor.”
We fear that many people assume over-the-counter products are super safe. Many don’t bother to read warnings, or if they do, they may ignore them. Your experience suggests that such warnings are there for a reason and suggests some healthy people should also be wary.
Reader Wonders Why Blood Pressure Is Rising:
Q. Can Preparation H raise blood pressure? I have been using Preparation H for a few weeks for a hemorrhoid problem. During that time it seems that my blood pressure has been going up.
My pressure has always been in the normal range of 120/80 or lower but now I’m seeing systolic numbers in the 130 to 140 range. I noticed that in the Prep H warning it mentions to ask your doctor before using it if you have high blood pressure.
A. One of the active ingredients in Preparation H is phenylephrine, a vasoconstrictor. This is the same drug that is used as a decongestant in some nasal sprays and oral cold medicines.
Vasoconstrictors work by contracting blood vessels and shrinking swollen tissues. One possible side effect is increased blood pressure. Anesthesiologists sometimes use phenylephrine to raise blood pressure during surgery if a patient’s blood pressure drops too low.
The rectum is well supplied with blood vessels. That is why suppositories are effective for delivering drugs into the blood stream. When phenylephrine is absorbed from these delicate tissues, it may raise blood pressure.
Learn More:
You can learn more about medications that raise blood pressure as well as ways to treat hypertension from our eGuide to Blood Pressure Solutions. You might also want to read about home remedies for treating hemorrhoids that others have tried.
Thanks to Chitra Shankar, PharmD, who reviewed and contributed to this post.
