In swallowing, one portion is volunatary and one part is involuntary. â¢ Buccal phase o Voluntary contraction of the tongue o Step 1 in figure â¢ Pharyngeal-esophageal phase o Involuntary o Control center in the medulla and lower pon o Step 2-5 in figure.
Considerations. Serotonin is a mood regulator that occurs naturally in the body. When serotonin levels are chemically altered, as they are with the use of diet supplements such as Phentermine, a chemical imbalance occurs that may lead to feelings of anxiety or depression.
There are many causes of depression. Having the diagnosis of a chronic disease, like HIV infection or AIDS, can make depressive symptoms worse. Some medications used to treat HIV can cause or worsen depression, especially efavirenz (Sustiva). Diseases such as anemia or diabetes can cause symptoms that look like depression. So can drug use, or low levels of testosterone, vitamin B6, or vitamin B12.