Anti-anxiety medications can relieve symptoms of anxiety and related disorders as a part of a treatment program under the guidance of a doctor or therapist. The National Institute of Mental Health advises that these psychiatric medications are also important in the treatment related conditions such as panic disorders, obsessive compulsive disorder, bipolar disorder and attention deficit hyperactivity disorder. The effects of anxiety medications include changes in dietary habits and body weight.
Benzodiazepines are anti-anxiety medications that are also known as tranquilizers. These potent medications help to reduce anxiety and related symptoms such as panic and nervousness, by subduing the central nervous system. This common class of anti-anxiety medications includes the brand name medications Xanax, Valium, Ativan and Klonopin. Benzodiazepines are fast-acting and typically affect the body within 30 minutes to an hour of taking a dose. However, they also have several side effects that can lead to weight loss. These include nausea, dizziness, vomiting and stomach upset that may cause a loss of regular appetite and make it difficult to keep ingested food down. These medications also build up in the body and are metabolized slowly, causing long-term side effects, including over-sedation with symptoms similar to being intoxicated due to alcohol.
Buspirone is a newer anti-anxiety drug that is prescribed under the brand name BuSpar. Healthy Place notes that this drug acts as a mild tranquilizer and decreases anxiety in a similar mechanism as anti-depressant medications such as selective serotonin reuptake inhibitors, or SSRIs. Though this medication is slower acting than benzodiazepines, it can cause side effects, including some that affect the gastrointestinal tract and digestion. HelpGuide.org lists these side effects to include nausea, vomiting, dry mouth, upset stomach, constipation and diarrhea. These side effects can lead to weight loss due to loss of appetite, taste and distress after eating.
Antidepressants drugs such as monoamine oxidase inhibitors, or MAOIs, are also used to treat anxiety in some individuals. MAOIs include the brand name medications Nardil and Parnate, and work by increasing levels of certain chemicals, or neurotransmitters, in the brain. Drugs.com notes that this class of drugs can cause several side effects that affect nutrition and digestion, resulting in weight loss. These include nausea, dizziness, dry mouth, upset stomach and stomach cramping. Additionally, MAOIs negatively interact with foods containing high levels of the amino acid tyramine, such as cheese, yogurt, sour cream, packaged soups, beer, wine and some vegetables. Eating these foods when taking MAOIs can cause pain, diarrhea, constipation or vomiting, and can be life threatening.