Buspirone, Buspar®

• Buspar ®

1. Ant-anxiety
2. Buspirone may work by stimulating serotonin type 1A receptors on nerves, thereby altering the chemical messages that nerves receive.
3. It also has minor effects on dopamine receptors but this does not contribute much to its action.
4. Unlike benzodiazepine, buspirone does not cause sedation.

1. Tablets: 5, 10, 15, and 30 mg

1. Management of anxiety disorders or for the short-term relief of the symptoms of anxiety
2. Generalized anxiety of a limited or moderate degree
3.  It may help improve symptoms of depression in patients with generalized anxiety disorder
4. It is not very effective in:
   1. Severe anxiety
   2. Panic disorders
   3. Obsessive-compulsive disorders

1. The usual starting adult dose is 10-15 mg daily in 2 or 3 divided doses.
2. The dose may be increased by 5 mg every 2 to 4 days until an effective dose is found.
3. The maximum adult dose is 60 mg daily, but most patients respond to 15-30 mg daily in 2 or 3 divided doses.
4. Although food increases the amount of buspirone that is absorbed, the importance of this effect is not clear. Buspirone should be taken with or without food on a consistent basis.

MAO inhibitors:

• Buspirone may interact with drugs called monoamine oxidase (MAO) inhibitors, such as isocarboxazid (Marplan), phenelzine (Nardil), tranylcypromine (Parnate), and procarbazine (Matulane) which are used in psychotic disorders.
• The use of buspirone with these drugs can cause increased blood pressure.

Trazodone:

• The combination of buspirone and trazodone (antidepressant) may cause abnormal liver enzymes in the blood.

Warfarin:

• The combination of buspirone and warfarin (Coumadin) may accentuate the effects of warfarin and increase the risk of bleeding.

Grapefruit juice:

• Patients taking buspirone should not drink grapefruit juice, since the juice (even well after a dose is taken) can increase the amount of buspirone in the blood, possibly leading to side effects.

Liver metabolism:

• Inactivation and removal of buspirone is mediated by liver enzymes. Drugs (for example, erythromycin, itraconazole [Sporanox], nefazodone [Serzone]) that inhibit these liver enzyme increase blood concentrations of buspirone
• Drugs (for example, rifampin) that enhance these enzymes decrease blood concentrations of buspirone. Increased blood concentrations may increase side effects while decreased blood concentrations may reduce efficacy.

• Skin rash
• Dizziness
• Nausea
• Headache
• Nervousness
• Lightheadedness
• Excitement
• Insomnia
• Unsteady gait
• Changes to bowel movements
• Weakness
• Hostility
• Tremors

• There are no adequate studies of buspirone in pregnant women
• It is not known if buspirone is secreted in human breast milk.
• Because buspirone is secreted in the breast milk of animals, however, it should not be used by women who are nursing infants.