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.
It is thought that the antidepressant effects of the drug are due to its actions on serotonin and norepinephrine. These are chemicals used to send messages in between nerves. However, if serotonin or norepinephrine levels become unbalanced, it can cause a variety of conditions, including depression.