Sedatives and hypnotics are medications that help patients relax. When used in dentistry, these drugs are generally given to patients before or during dental procedures and may be taken in pills, liquids, by injection or inhalation. While these drugs do not control pain, they do provide patients with a sense of calm that makes it much easier to endure certain procedures.

Sedatives and hypnotics are usually considered one class of medication. Sedatives can mentally and physically relax the body. Hypnotics may induce sleep. Some medications in this class have both effects on the body, while others do not.

Some patients feel little or no anxiety prior to dental procedures. However, other patients may experience great nervousness prior to visiting the dentist. Such patients are urged to express these concerns to their dentist. In some cases, the dentist will suggest that the patient take a form of sedative and hypnotic that will help bring on a sense of relaxation.

Certain cases of anxiety can be treated with an anti-anxiety medication (e.g., benzodiazepines) that is taken in pill form. These drugs are often taken anywhere from the night before a procedure to 30 minutes prior to the procedure.

Deeper levels of sedation may be required for patients who are particularly anxious or for those who are to undergo complex procedures. Young children and mentally or physically challenged patients (e.g., patients with mental retardation, cerebral palsy) also may need deeper levels of sedation before certain procedures. These sedatives often are given in combination with local anesthesia, which prevents a patient from feeling pain during dental work such as fillings, crowns, root canals and extractions. There are four major levels of sedation. They are:

• Anxiolysis. Light sedation that makes patients feel as if they have no worries. Patients can respond to commands given by the dentist with this method and are able to feel touch. This sedative is usually administered orally.
  
  
• Conscious sedation. A medium level of sedation in which patients feel relaxed and in control of their own breathing, but are groggier than in anxiolysis. Patients can still respond to speech and touch. The gag reflex is generally intact. This sedative is usually administered intravenously (through a vein).
  
  
• Deep sedation. A level of sedation that places the patient somewhere between consciousness and unconsciousness. Patients are more deeply sedated than in conscious sedation and may experience a partial loss of the gag reflex and an inability to respond well to commands or stimulation. In some cases, patients may need help breathing. This sedative is always administered intravenously.
  
  
• General anesthesia. Patients are completely unconscious and do not feel any pain. They cannot respond to commands or stimuli and need a tube to help them breathe because the gag reflex is absent. This sedative is always administered intravenously.

Techniques that may be used to sedate patients include:

• Nitrous oxide. Often called laughing gas, this sedative mixes nitrous oxide with oxygen and is inhaled through a mask. The effects of nitrous oxide wear off soon after removing the oxygen mask, and few people experience side effects. Nitrous oxide is often used to induce sedation at the anxiolysis and conscious sedation levels.
  
  
• Intravenous (I.V.) sedation. This technique involves introducing a sedative through a needle inserted into a vein, usually in the arm. Depending on the type of drugs and dosages of drugs used, I.V. sedation can range from conscious sedation to deep sedation to general anesthesia. Patients may experience a 15- to 20-minute recovery period following the procedure.