Anxiolytic means preventing or lessening anxiety, and usually refers to any anti-anxiety drug.
Benzodiazepines, barbiturates, muscle relaxants, selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs), monoamine oxidase inhibitors (MAOIs), beta-blockers, and atypical antidepressants are all anxiolytics used to treat anxiety and to produce feelings of relaxation and calmness.
Barbiturates, such as Phenobarbital and Seconal, were mostly replaced by benzodiazepines in the 1960s. These newer drugs were considered less habit-forming and safer than barbiturates. Barbiturates are tricky to prescribe and use, and it is easy to overdose on them. In some cases, if you increase your dosage by just a tiny amount, you can die. Barbiturates are today mostly prescribed for epilepsy and other seizure disorders, not anxiety.
Benzodiazepines include some very popular brands like Valium, Halcion, Restoril, Xanax, Ativan, Librium, and Klonopin. Side effects can be confusion, depression, insomnia, mood changes, tremors, muscle cramps, menstrual changes, sexual dysfunction, anorexia, hypotension, and problems with urination. Benzodiazepines are widely prescribed and widely abused, and account for five of the top most abused drugs in the United States. They are very addictive, and can result in a very unpleasant withdrawal syndrome that is difficult to manage without professional help. Symptoms can last two weeks and include anxiety, tremors, nightmares, vomiting, nausea, low blood pressure, seizures, fever, and visual and auditory hallucinations.
Other kinds of anxiolytics include SSRIs, which are considered safer and less addictive than benzodiazepines or barbiturate. However, some new studies indicate they only work on major, and not minor, cases of depression. They work by blocking the reuptake of serotonin in the brain without affecting other brain chemicals, which is why they are called “selective serotonin reuptake inhibitors”. Some trademarked brands are Prozac, Symbyax, Paxil, Zoloft, Lexapro, and Celexa.