The prescription medication prazosin -- sold under the brand name of Minipress -- is a drug used to treat nightmares in the setting of post-traumatic stress disorder (PTSD).
Uses of Prazosin
Prazosin works by blocking specialized chemical receptors (called alpha-1 receptors) at the surface of cells. It is commonly used to treat benign prostatic hypertrophy, and is also effective in treating nightmares in the setting of post-traumatic stress disorder (PTSD).
How Does Prazosin Work?
As described above, prazosin acts at the site of cell receptors. Receptors are the sites where messages are transmitted from one cell to the next. It is not clear how this specifically may impact sleep or dreams.
Who Should Not Use Prazosin?
Prazosin appears to be a relatively safe medication, and there are only a few circumstances where it should not be used or should be used with caution. If you have previously had adverse reactions to this or similar medications, prazosin should not be used. Also, if you have had cataract surgery, the medication should be used with caution. Your doctor can help you determine whether these circumstances apply to you.
What Are Common Side Effects of Prazosin?
There are potential side effects with the use of any medication, and prazosin is no exception. Although you are not likely to experience most side effects -- and may indeed not have any of them -- some that commonly occur with prazosin include:
- Hypotension (low blood pressure)
- Loss of strength
- Palpitations (irregular heartbeats)
- Priapism (sustained painful erection)
- Urinary frequency
- Shortness of breath
- Muscle and joint pains
What Are Potential Serious Reactions of Prazosin?
With the use of any drug, there are also risks of serious side effects. These occur more rarely, but with the use of prazosin may include:
- Syncope (fainting)
- Intraoperative floppy iris syndrome (loss of muscle tone in the colored part of the eye)
What Safety Precautions Need to Be Taken with Prazosin?
As described above, certain people should use prazosin with caution or not at all. The safety of its use with pregnancy or breastfeeding is not known, so caution is advised. It may be important to monitor your blood pressure with its use, so that it does not become too low and cause fainting or falls. If you experience any difficulties, you should be in close contact with your primary health care provider.
"Prazosin." Epocrates Rx Pro. Version 2.90, 2009. Epocrates, Inc. San Mateo, California.