LO 14 Flashcards
Anti Anxiety drugs
1
Q
How is the need for anty-anxiety drugs assessed?
A
- Objectively assessing the patient’s anxiety is necessary on both the first and subsequent visits
- The dosing of a particular antianxiety agent is vastly variable, involving intrapatient and interpatient variation
2
Q
Anxiety is best managed by __________
A
A calm, confident approach
3
Q
What are the signs of anxiety?
A
- clutching - “white knuckle”
- Low pain threshold with high anxiety
4
Q
List the range of effects of anti-anxiety drugs with increasing dose
A
- Sedative (this is as far down the list as we want to get)
- Euphoria
- Lethargy
- Hypnosis
- Anesthesia
- Death
*Anti-anxiety drugs are CNS depressants
5
Q
What are the 2 types of anti-anxiety drugs used in dental?
A
- Benzodiazepines (minor tranquilizers)
- Barbiturates (not used any longer in dentistry as anti-anxiety meds - addictive and often abused)
6
Q
Describe Benzodiazepines
A
- Minor tranquilizers
- Less abuse than barbs
- Wide therapeutic index (TI)
- Valium (diazepam)
- Ativan (lorazepam)
- Taken 1/2 hr before the appointment
7
Q
Describe the mechanism of action for Benzodiazepines
A
- Benzodiazepines enhance GABA action; a major inhibitory neurotransmitter. result: The inhibitor effect of GABA is enhanced
- Vary in onset and duration - can be short or long acting, can be rapid or slow onset
- Valium and Ativan are on the short, rapid side
8
Q
Describe the pharmkinetics (ADME) of Benzodiazepines
A
- Absorption - GI (high lipid solubility)
Cross all barriers (BBB and placenta) - Metabolism - liver
- 1/2 life - anywhere from minutes to 200 hours
9
Q
Describe the pharm effects and med uses for Benzodiazepines
A
- Behavioral management - short-term treatment of anxiety, panic attacks, insomnia, and alcohol withdrawal
- Anti-seizure (Increase the seizure threshold) - Tx of epilepsy
- Muscle relaxation of skeletal muscles - muscle control in multiple sclerosis & cerebral palsy; Used for conscious sedation, general anesthesia
10
Q
List the adverse reactions of Benzodiazepines
A
- CNS - CNS depression (usually):
manifested as fatigue, drowsiness, muscle weakness, and ataxia; CNS excitement (occasionally) - Amnesia - give POI (post-operative instructions) in writing; warn against signing important papers under the influence
- Respiratory - Resp depression especially with diazepam
- CVS - Relief of anxiety may result in a fall in blood pressure and pulse rate (typically to a normal rate)
- Visual effects - do not use if pt has certain types of glaucoma - can produce diplopia (single object viewed as two)
- Dental/oral - Xerostomia, Macroglossia, Bitter metallic taste
- Thrombophlebitis - Parenteral (IV) diazepam may cause thrombophlebitis because propylene glycol is used to solubilize it
- Other - GI cramps; GU: decrease urination (Think “ anticholinergic” effects (anti SLUD)); Allergic reaction
- Pregnancy - Cross all barriers; Highly teratogenic (higher cleft lip/palate)
- Abuse/tolerance - With chronic use physical dependence and tolerance have been documented
11
Q
What are the significant drug-drug interactions with Benzodiazepines?
A
- Benzodiazepines will interact in an additive fashion with other CNS depressants - Et-OH, Narcotics, phenothiazine (anti-psychotics)
- They will also - Increase efficacy of phenytoin; Increase digoxin toxicity
12
Q
What are the special considerations of benzos?
A
- Patients who are to use antianxiety agents should be driven to and from the dental appointment
- Drugs are not a substitute for patient management
- Drugs should not be substituted for patient education or for the proper psychologic approach to patient care
13
Q
Describe the treatment of bezo overdose
A
- Emesis - have patient vomit in a bowl so the number of intact pills can be counted
- Antidote (benzodiazepine antagonist):
Flumazenil
14
Q
Parenteral benzodiazepines have been associated with ___________ when used for conscious sedation. Therefore, patients require _________. Dentists without additional training cannot use conscious sedation
A
- respiratory depression and arrest
- continuous monitoring of respiratory and cardiac function
15
Q
Describe Barbiturates
A
- Chronic use of barbiturates can lead to physical and psychologic dependence
- They cross all barriers
- Mech of action: enhance GABA receptor binding
16
Q
What are the medical uses for Barbiturates?
A
- GA induction: (ultra short acting):
thiopental - Tx of epilepsy phenobarbital
17
Q
List the contraindications of Barbiturates
A
- Porphyria - a group of disorders involving heme biosynthesis
- Barbiturates are absolutely contraindicated in patients with intermittent porphyria or a positive family history of porphyria
- Barbiturates can stimulate and increase the synthesis of porphyrins which are already at an excessive level in this disease
18
Q
Describe the drug interactions of Barbiturates
A
- Additive drug interaction with other CNS depressants
- stimulators of liver microsomal enzyme production: increasing the rate of other drugs metabolism/ destruction and subsequently decreasing the duration of their action
- cross-tolerance with benzodiazepines (more barbiturates must be given to pt with previous exposure to benzodiazepines)
19
Q
Describe buspirone (BuSpar)
A
- Selective Anxiolytic - Selective means it is only blocking certain pathways and not others - good thing that allows people to function more normally while on it
- New medication and patients don’t particularly like it - therefore it is not widely prescribed -Most patients prefer the benzodiazepines
- Anxioselective without hypnotic, anticonvulsant, or muscle-relaxant properties
- No effect on CNS → driving is OK
20
Q
List the precautions of anti-anxiety drugs
A
- Patients with impaired elimination (kidney disfunction) may experience exaggerated effects of these medications
- Depression caused by all sedative-hypnotics will add to depression caused by other CNS depressants
- The patient should be accompanied by a responsible adult who can drive the patient home
- Psychic and physical dependence has been observed with almost all drugs used to allay anxiety
- Suicide may be attempted by taking sedative-hypnotic drugs
- These drugs should never be administered to pregnant women or to those who may be pregnant unless the potential benefit to the mother outweighs the risk to the fetus
- Sedatives do not provide analgesia
