Hypnotics and Anxiolytics: Part 7.

Hydroxyzine is a another medication used in the treatment of anxiety disorders. It belongs to antihistamines group, and possess a distinct anti-emetics activity.

MOA: Hydroxyzine competes with histamine for histamine receptors (H-1), thus blocking the effects of histamine. It produces brochodilation and relaxation of skeletal muscles.

ADR:

• Drowsiness.
• CNS depression.
• Paradoxical CNS stimulation.
• Dry mouth.
• Constipation.
• Blurry vision.
• GI disturbances.
• Tachycardia.

TU:

• Mild to severe anxiety, particularly used in drug abusers due to low tendency of habituation.

PRCTN:

• Pregnant and lactating mothers.
• Porphyric patients.
• Renal and liver impairment.

The next drug would be Zolpidem, commonly used to treat both anxiety and insomniac patients.

MOA: Zolpidem acts on the subdivision of benzodiazepines receptors in CNS. It produces hypnotic effects, accompanied by strong sedation. However, the duration of action is short.

ADR:

• Nightmares.
• Agitation.
• Headache.
• GI upset.
• Dizziness.
• Daytime drowsiness.
• Euphoria.
• Vertigo.
• Confusion.

TU:

• Treatment of mild anxiety and insomnia.

PRCTN:

• Pregnant and lactating mothers.
• Obstructive sleep apnea.
• Renal and hepatic impairment.
• Myasthenia gravis.

The last type of drug used in the treatment of anxiety disorder is Zaleplon. It is also a common medication given to patients with insomnia.

MOA: Interact with GABA sub-complex type A by binding selectively with benzodiazepine-1 receptor to produce sedative and hypnotic effects.

ADR:

• Dry mouth.
• Asthenia.
• Headaches.
• Light-headedness.
• Dizziness.
• Myalgia.
• Fever.
• Migraine. 

TU:

• Treatment of anxiety and insomniac disorders.

PRCTN:

• Pregnant and lactating mothers.
• Hypersensitivity.
• Severe hepatic impairment.

Less used medications for these anxiety disorders include chloral hydrate and ethanol. Chloral hydrate produces both sedative and hypnotic effects that lasts about 30 minutes. On the other hand, ethanol is not used today due to the toxic effects that can be percipitated.

MOA: Depress the CNS via its metabolite, trichloroethanol.

ADR:

• Gastric irritation.
• Vertigo.
• Ataxia.
• Ketonuria.
• Eosinophilia.

TU:

• Treatment of insomnia and mild anxiety.

PRCTN:

• Pregnant and lactating mothers.
• Cardiac disorder patients.
• Hepatic or renal impairment.
• Porphyric patients.
• Gastritis patients.

This marks the end of this topic. If you have any questions, feel free to ask in the comment form below and I'll get back to you as soon as I can.