As a result, depression treatment increasingly relies on drugs that moderate levels of certain compounds in the nervous system.
Most drugs used to treat depression work by increasing the amount of serotonin or dopamine available in the body. These chemicals regulate how cells within the brain talk to one another and help coordinate interactions between different brain regions.
Low levels of serotonin and dopamine have been linked to alterations in mood, and antidepressant drugs are designed to increase the available amount of these chemicals.
The Role of Neurochemicals
Serotonin and dopamine play important roles in many parts of the body outside the brain, and antidepressant drugs are increasingly used to treat a variety of conditions such as chronic pain.
Both of these compounds are known to affect the heart and blood vessels.
In concentrated doses, dopamine is used as an emergency drug to increase blood pressure during surgery and when certain conditions—such as body-wide infection—lead to low blood pressure beyond the body’s ability to correct.
To a lesser extent, serotonin has similar blood-pressure-raising effects and may increase how sensitive the heart and vessels are to effects of dopamine .
Concerns About Antidepressants
While antidepressants don’t increase serotonin and dopamine to extreme levels, their use has been known to raise blood pressure. Specific antidepressants that have been linked to increased blood pressure include:
Effexor XR (venlafaxine) Monoamine oxidase inhibitors Tricyclic antidepressants Prozac, Sarafem (fluoxetine)
Increased levels of serotonin and dopamine play an important role in how these drugs raise blood pressure, but there is probably more to the story, and the precise mechanisms are still a matter of some debate.
Current thinking is that these drugs increase overall activity in the nervous system, which might amplify certain signals (such as those controlling blood pressure) that the nervous system sends to the rest of the body.
It’s also important to note that depression is linked to low blood pressure (and anxiety to high blood pressure). Therefore, correcting the underlying depression may “normalize” blood pressure, which for some people may tend toward the high normal or even low abnormal range.
Blood Pressure Management
If you have high blood pressure, you can still use antidepressant medications. Your healthcare provider may choose to avoid certain types of antidepressants, though, and will likely want to monitor your blood pressure carefully during the initial stages of treatment.
Many people with high blood pressure are able to use the most common antidepressants with no problems, but some may require adjustments to their high blood pressure treatment program.
If you require an antidepressant, finding the right medication—or combination of medications—can be a trial-and-error process. The goal of any treatment plan is for the benefits to outweigh the risks or side effects.
