{"id":374,"date":"2019-11-19T16:58:42","date_gmt":"2019-11-19T16:58:42","guid":{"rendered":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/chapter\/8-5-cns-depressants\/"},"modified":"2021-12-07T11:26:11","modified_gmt":"2021-12-07T11:26:11","slug":"8-5-cns-depressants","status":"publish","type":"chapter","link":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/chapter\/8-5-cns-depressants\/","title":{"raw":"8.5 CNS Depressants","rendered":"8.5 CNS Depressants"},"content":{"raw":"
\n\nBarbiturates and benzodiazepines are examples of CNS depressants.\n

Barbiturates<\/h2>\nPhenobarbital is an example of a barbiturate primarily used as a sedative and to treat seizure disorders. In high doses it can be used to induce anesthesia, and overdosage can cause death. In the 1960s and 1970s, barbiturates were used to treat anxiety and insomnia, but are no longer used for these purposes due to their serious adverse effects. Barbiturates are a Schedule IV drug under the Federal Controlled Substances Act. However, the abuse of barbiturates continues to occur with street use as a \u201cdowner\u201d to counteract the effect of cocaine and methamphetamine.\n\nMechanism of Action<\/strong>\n\nBarbiturates produce sedation and drowsiness by altering cerebellar function and depressing the actions of the brain and sensory cortex.\n\nIndications for Use<\/strong>\n\nBarbiturates are primarily used for sedation and seizures.\n\nNursing Considerations Across the Lifespan<\/strong>\n\nDo not use for children less than 1 month of age. Barbiturates may harm the fetus during pregnancy. Avoid use in geriatic patients.\n\nAdverse\/Side Effects<\/strong>\n\nPatients may experience CNS depression, suicidal thoughts or behaviors, GI disturbances, rashes, or some blood disorders that can be fatal. The concomitant use of alcohol or other CNS depressants may produce additive CNS depressant effects that can cause death. It can be habit forming.\n\nPatient Teaching & Education<\/strong>\n\nThe patient should be advised to take the prescribed medication as directed.\u00a0 Patients who undergo prolonged therapy should not discontinue treatment abruptly as this may cause onset of seizure activity.\u00a0 These medications may cause drowsiness and should not be taken with alcohol or other CNS depressants.\u00a0 Female patients using oral contraceptives should also use non-hormonal based contraceptives during therapy.\n\nOverdosage<\/strong>\n\nThe onset of symptoms following a toxic oral exposure to phenobarbital may not occur until several hours following ingestion. If overdose occurs, consult with a Certified Poison Control Center (1-800-222-1222) or go to https:\/\/www.poisonhelp.org\/help<\/a> for the latest recommendations.[footnote]This work is a derivative of Daily Med<\/a> by U.S. National Library of Medicine<\/a> in the public domain<\/a>. \u00a0[\/footnote],[footnote]Drugs.com (2019, February 5). Barbiturates<\/em>. https:\/\/www.drugs.com\/drug-class\/barbiturates.html<\/a>[\/footnote]<\/sup>\n\nNow let's take a closer look at the medication grid for phenobarbital in Table 8.5a.[footnote]This work is a derivative of Daily Med<\/a> by U.S. National Library of Medicine<\/a> in the public domain<\/a>. [\/footnote]<\/sup> Medication grids are intended to assist students to learn key points about each medication class.\u00a0 Basic information related to a common generic medication in this class is outlined, including administration considerations, therapeutic effects, and side effects\/adverse effects.\u00a0 Prototype\/generic medication listed in the med grid is also hyperlinked directly to a free resource from the U.S. National Library of Medicine called Daily Med.\u00a0 Because information about medication is constantly changing, nurses should always consult evidence-based resources to review current recommendations before administering specific medication.\n\nTable 8.5a Phenobarbital Medication Grid\n\n\n\n\n
Class\/<\/strong>\n\nSubclass<\/strong><\/th>\nPrototype\/<\/strong>\n\nGeneric<\/strong><\/th>\nAdministration<\/strong>\n\nConsiderations<\/strong><\/th>\nTherapeutic Effects<\/strong><\/th>\nAdverse\/Side Effects<\/strong><\/th>\n<\/tr>\n
Barbiturates<\/th>\nphenobarbital<\/a><\/td>\nMay be administered orally, IM, or IV\n\nHigh abuse potential\n\nShould not be combined with other CNS depressants\n\nWhen therapy is discontinued, the dose should be tapered and not stopped abruptly<\/td>\nPrimarily used as an anticonvulsant\n\nAlso used as a sedative and may also be used as a preanesthetic agent<\/td>\nCNS depression; overdosage can cause death\n\nMay cause suicidal thoughts or behavior\n\nRespiratory depression\n\nGI: Nausea and vomiting<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n \n

Benzodiazepines<\/h2>\nLorazepam, a benzodiazepine with antianxiety, sedative, and anticonvulsant effects, is available for oral, intramuscular, or intravenous routes of administration. Benzodiazepines are a controlled Schedule IV substance because they have a potential for abuse and may lead to dependence.\n\nMechanism of Action<\/strong>\n\nBenzodiazepines bind to specific GABA receptors to potentiate effects of GABA.\n\nIndications for Use<\/strong>\n\nBenzodiazepines are used for sedation, antianxiety, and anticonvulsant effects. Lorazepam injection is indicated for the treatment of status epilepticus. It may also be used in adult patients for preanesthetic medication to produce sedation (sleepiness or drowsiness), relieve anxiety, and decrease the ability to recall events related to the day of surgery. Oral lorazepam is used to treat anxiety disorders.\n\nNursing Considerations Across the Lifespan<\/strong>\n\nBenzodiazepines may cause fetal harm when administered to pregnant women. Children and the elderly are more likely to experience paradoxical reactions to benzodiazepines such as tremors, agitation, or visual hallucinations. Elderly or debilitated patients may be more susceptible to the sedative and respiratory depressive effects of lorazepam. Therefore, these patients should be monitored frequently and have their dosage adjusted carefully according to patient response; the initial dosage should not exceed 2 mg. Dosage for patients with severe hepatic insufficiency should be adjusted carefully according to patient response.\n\nAdverse\/Side Effects<\/strong>\n\nA Black Box Warning states that concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma, and death.\n\nThe most important risk associated with the intravenous use of lorazepam injection is respiratory depression. Accordingly, airway patency must be assured and respiration monitored closely. Ventilatory support should be given as required. The additive central nervous system effects of other drugs, such as phenothiazines, narcotic analgesics, barbiturates, antidepressants, scopolamine, and monoamine-oxidase inhibitors should be considered when these other drugs are used concomitantly with, or during the period of recovery from, lorazepam injection. Sedation, drowsiness, respiratory depression (dose dependant), hypotension, and unsteadiness may occur with oral dosages as well. The use of benzodiazepines may lead to physical and psychological dependence. Abrupt termination of treatment may be accompanied by withdrawal symptoms. Benzodiazepines should be prescribed for short periods only (e.g., 2 to 4 weeks). Extension of the treatment period should not take place without reevaluation of the need for continued therapy.\n\nOverdosage<\/strong>\n\nOverdosage of benzodiazepines is usually manifested by varying degrees of central nervous system depression, ranging from drowsiness to coma. Treatment of overdosage is mainly supportive until the drug is eliminated from the body. Vital signs and fluid balance should be carefully monitored in conjunction with close observation of the patient. An adequate airway should be maintained and assisted respiration used as needed. The benzodiazepine antagonist flumazenil may be used in hospitalized patients in the management of benzodiazepine overdose. There is a risk of seizure in association with flumazenil treatment, particularly in long-term benzodiazepine users. If overdose occurs, consult with a Certified Poison Control Center (1-800-222-1222) or go to https:\/\/www.poisonhelp.org\/help<\/a> for the latest recommendations.\n\nPatient Teaching & Education<\/strong>\n\nPatients who receive lorazepam should be cautioned that driving a motor vehicle, operating machinery, or engaging in hazardous or other activities requiring attention and coordination should be delayed for 24 to 48 hours following administration or until the effects of the drug, such as drowsiness, have subsided. Patients should be advised that getting out of bed unassisted may result in falling and potential injury if undertaken within 8 hours of receiving lorazepam. Alcoholic beverages should not be consumed for at least 24 to 48 hours after receiving lorazepam injectable due to the additive effects on central nervous system depression seen with benzodiazepines in general. Elderly patients should be instructed that lorazepam injection may make them very sleepy for a period longer than 6 to 8 hours following surgery.\n\nNow let's take a closer look at the medication grid for lorazepam in Table 8.5b.[footnote]This work is a derivative of Daily Med<\/a> by U.S. National Library of Medicine<\/a> in the public domain<\/a>.[\/footnote]<\/sup>\n\nTable 8.5b Lorazepam Medication Grid\n\n\n\n\n
Class\/<\/strong>\n\nSubclass<\/strong><\/th>\nPrototype\/<\/strong>\n\nGeneric<\/strong><\/th>\nAdministration <\/strong>Considerations<\/strong><\/th>\nTherapeutic Effects<\/strong><\/th>\nAdverse\/Side Effects<\/strong><\/th>\n<\/tr>\n
Benzodiazepines<\/th>\nlorazepam<\/a><\/td>\nBlack Box Warning: Concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma, and death\n\nMay cause fetal harm in pregnant women\n\nMay cause paradoxical effect in children\n\nUse cautiously in elderly and with those with liver dysfunction<\/td>\nTo relieve anxiety, reduce seizure activity, or as a preanesthetic<\/td>\nOversedation and drowsiness\n\nRespiratory depression\n\nUnsteadiness and fall risk\n\nOverdosage can cause coma and death\n\nFlumazenil used for overdose<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n \n\n<\/div>\n
\n
\n

Critical Thinking Activity 8.5\n\"Image<\/h2>\n<\/header>\n
\n\nA patient who has been experiencing panic attacks is prescribed lorazepam. Upon further discussion with the patient, the nurse discovers that the patient is planning to go on a cruise with her husband next week and plans to use a scopolamine patch to control the nausea. The patient states, \u201cI can\u2019t wait to relax on the cruise ship and have a margarita as we leave port!\u201d\n\nWhat important patient education should the nurse provide to the patient about the new prescription for lorazepam?\n\nNote: Answers to the Critical Thinking activities can be found in the \"Answer Key\" sections at the end of the book.\n\n<\/div>\n<\/div>\n<\/div>","rendered":"
\n

Barbiturates and benzodiazepines are examples of CNS depressants.<\/p>\n

Barbiturates<\/h2>\n

Phenobarbital is an example of a barbiturate primarily used as a sedative and to treat seizure disorders. In high doses it can be used to induce anesthesia, and overdosage can cause death. In the 1960s and 1970s, barbiturates were used to treat anxiety and insomnia, but are no longer used for these purposes due to their serious adverse effects. Barbiturates are a Schedule IV drug under the Federal Controlled Substances Act. However, the abuse of barbiturates continues to occur with street use as a \u201cdowner\u201d to counteract the effect of cocaine and methamphetamine.<\/p>\n

Mechanism of Action<\/strong><\/p>\n

Barbiturates produce sedation and drowsiness by altering cerebellar function and depressing the actions of the brain and sensory cortex.<\/p>\n

Indications for Use<\/strong><\/p>\n

Barbiturates are primarily used for sedation and seizures.<\/p>\n

Nursing Considerations Across the Lifespan<\/strong><\/p>\n

Do not use for children less than 1 month of age. Barbiturates may harm the fetus during pregnancy. Avoid use in geriatic patients.<\/p>\n

Adverse\/Side Effects<\/strong><\/p>\n

Patients may experience CNS depression, suicidal thoughts or behaviors, GI disturbances, rashes, or some blood disorders that can be fatal. The concomitant use of alcohol or other CNS depressants may produce additive CNS depressant effects that can cause death. It can be habit forming.<\/p>\n

Patient Teaching & Education<\/strong><\/p>\n

The patient should be advised to take the prescribed medication as directed.\u00a0 Patients who undergo prolonged therapy should not discontinue treatment abruptly as this may cause onset of seizure activity.\u00a0 These medications may cause drowsiness and should not be taken with alcohol or other CNS depressants.\u00a0 Female patients using oral contraceptives should also use non-hormonal based contraceptives during therapy.<\/p>\n

Overdosage<\/strong><\/p>\n

The onset of symptoms following a toxic oral exposure to phenobarbital may not occur until several hours following ingestion. If overdose occurs, consult with a Certified Poison Control Center (1-800-222-1222) or go to https:\/\/www.poisonhelp.org\/help<\/a> for the latest recommendations.[1]<\/sup><\/a>,[2]<\/sup><\/a><\/sup><\/p>\n

Now let’s take a closer look at the medication grid for phenobarbital in Table 8.5a.[3]<\/sup><\/a><\/sup> Medication grids are intended to assist students to learn key points about each medication class.\u00a0 Basic information related to a common generic medication in this class is outlined, including administration considerations, therapeutic effects, and side effects\/adverse effects.\u00a0 Prototype\/generic medication listed in the med grid is also hyperlinked directly to a free resource from the U.S. National Library of Medicine called Daily Med.\u00a0 Because information about medication is constantly changing, nurses should always consult evidence-based resources to review current recommendations before administering specific medication.<\/p>\n

Table 8.5a Phenobarbital Medication Grid<\/p>\n\n\n\n\n
Class\/<\/strong><\/p>\n

Subclass<\/strong><\/th>\n

Prototype\/<\/strong><\/p>\n

Generic<\/strong><\/th>\n

Administration<\/strong><\/p>\n

Considerations<\/strong><\/th>\n

Therapeutic Effects<\/strong><\/th>\nAdverse\/Side Effects<\/strong><\/th>\n<\/tr>\n
Barbiturates<\/th>\nphenobarbital<\/a><\/td>\nMay be administered orally, IM, or IV<\/p>\n

High abuse potential<\/p>\n

Should not be combined with other CNS depressants<\/p>\n

When therapy is discontinued, the dose should be tapered and not stopped abruptly<\/td>\n

Primarily used as an anticonvulsant<\/p>\n

Also used as a sedative and may also be used as a preanesthetic agent<\/td>\n

CNS depression; overdosage can cause death<\/p>\n

May cause suicidal thoughts or behavior<\/p>\n

Respiratory depression<\/p>\n

GI: Nausea and vomiting<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n

Benzodiazepines<\/h2>\n

Lorazepam, a benzodiazepine with antianxiety, sedative, and anticonvulsant effects, is available for oral, intramuscular, or intravenous routes of administration. Benzodiazepines are a controlled Schedule IV substance because they have a potential for abuse and may lead to dependence.<\/p>\n

Mechanism of Action<\/strong><\/p>\n

Benzodiazepines bind to specific GABA receptors to potentiate effects of GABA.<\/p>\n

Indications for Use<\/strong><\/p>\n

Benzodiazepines are used for sedation, antianxiety, and anticonvulsant effects. Lorazepam injection is indicated for the treatment of status epilepticus. It may also be used in adult patients for preanesthetic medication to produce sedation (sleepiness or drowsiness), relieve anxiety, and decrease the ability to recall events related to the day of surgery. Oral lorazepam is used to treat anxiety disorders.<\/p>\n

Nursing Considerations Across the Lifespan<\/strong><\/p>\n

Benzodiazepines may cause fetal harm when administered to pregnant women. Children and the elderly are more likely to experience paradoxical reactions to benzodiazepines such as tremors, agitation, or visual hallucinations. Elderly or debilitated patients may be more susceptible to the sedative and respiratory depressive effects of lorazepam. Therefore, these patients should be monitored frequently and have their dosage adjusted carefully according to patient response; the initial dosage should not exceed 2 mg. Dosage for patients with severe hepatic insufficiency should be adjusted carefully according to patient response.<\/p>\n

Adverse\/Side Effects<\/strong><\/p>\n

A Black Box Warning states that concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma, and death.<\/p>\n

The most important risk associated with the intravenous use of lorazepam injection is respiratory depression. Accordingly, airway patency must be assured and respiration monitored closely. Ventilatory support should be given as required. The additive central nervous system effects of other drugs, such as phenothiazines, narcotic analgesics, barbiturates, antidepressants, scopolamine, and monoamine-oxidase inhibitors should be considered when these other drugs are used concomitantly with, or during the period of recovery from, lorazepam injection. Sedation, drowsiness, respiratory depression (dose dependant), hypotension, and unsteadiness may occur with oral dosages as well. The use of benzodiazepines may lead to physical and psychological dependence. Abrupt termination of treatment may be accompanied by withdrawal symptoms. Benzodiazepines should be prescribed for short periods only (e.g., 2 to 4 weeks). Extension of the treatment period should not take place without reevaluation of the need for continued therapy.<\/p>\n

Overdosage<\/strong><\/p>\n

Overdosage of benzodiazepines is usually manifested by varying degrees of central nervous system depression, ranging from drowsiness to coma. Treatment of overdosage is mainly supportive until the drug is eliminated from the body. Vital signs and fluid balance should be carefully monitored in conjunction with close observation of the patient. An adequate airway should be maintained and assisted respiration used as needed. The benzodiazepine antagonist flumazenil may be used in hospitalized patients in the management of benzodiazepine overdose. There is a risk of seizure in association with flumazenil treatment, particularly in long-term benzodiazepine users. If overdose occurs, consult with a Certified Poison Control Center (1-800-222-1222) or go to https:\/\/www.poisonhelp.org\/help<\/a> for the latest recommendations.<\/p>\n

Patient Teaching & Education<\/strong><\/p>\n

Patients who receive lorazepam should be cautioned that driving a motor vehicle, operating machinery, or engaging in hazardous or other activities requiring attention and coordination should be delayed for 24 to 48 hours following administration or until the effects of the drug, such as drowsiness, have subsided. Patients should be advised that getting out of bed unassisted may result in falling and potential injury if undertaken within 8 hours of receiving lorazepam. Alcoholic beverages should not be consumed for at least 24 to 48 hours after receiving lorazepam injectable due to the additive effects on central nervous system depression seen with benzodiazepines in general. Elderly patients should be instructed that lorazepam injection may make them very sleepy for a period longer than 6 to 8 hours following surgery.<\/p>\n

Now let’s take a closer look at the medication grid for lorazepam in Table 8.5b.[4]<\/sup><\/a><\/sup><\/p>\n

Table 8.5b Lorazepam Medication Grid<\/p>\n\n\n\n\n
Class\/<\/strong><\/p>\n

Subclass<\/strong><\/th>\n

Prototype\/<\/strong><\/p>\n

Generic<\/strong><\/th>\n

Administration <\/strong>Considerations<\/strong><\/th>\nTherapeutic Effects<\/strong><\/th>\nAdverse\/Side Effects<\/strong><\/th>\n<\/tr>\n
Benzodiazepines<\/th>\nlorazepam<\/a><\/td>\nBlack Box Warning: Concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma, and death<\/p>\n

May cause fetal harm in pregnant women<\/p>\n

May cause paradoxical effect in children<\/p>\n

Use cautiously in elderly and with those with liver dysfunction<\/td>\n

To relieve anxiety, reduce seizure activity, or as a preanesthetic<\/td>\nOversedation and drowsiness<\/p>\n

Respiratory depression<\/p>\n

Unsteadiness and fall risk<\/p>\n

Overdosage can cause coma and death<\/p>\n

Flumazenil used for overdose<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n<\/div>\n

\n
\n
\n

Critical Thinking Activity 8.5
\n\"Image<\/h2>\n<\/header>\n
\n

A patient who has been experiencing panic attacks is prescribed lorazepam. Upon further discussion with the patient, the nurse discovers that the patient is planning to go on a cruise with her husband next week and plans to use a scopolamine patch to control the nausea. The patient states, \u201cI can\u2019t wait to relax on the cruise ship and have a margarita as we leave port!\u201d<\/p>\n

What important patient education should the nurse provide to the patient about the new prescription for lorazepam?<\/p>\n

Note: Answers to the Critical Thinking activities can be found in the “Answer Key” sections at the end of the book.<\/p>\n<\/div>\n<\/div>\n<\/div>\n

  1. This work is a derivative of Daily Med<\/a> by U.S. National Library of Medicine<\/a> in the public domain<\/a>. \u00a0 ↵<\/a><\/li>
  2. Drugs.com (2019, February 5). Barbiturates<\/em>. https:\/\/www.drugs.com\/drug-class\/barbiturates.html<\/a> ↵<\/a><\/li>
  3. This work is a derivative of Daily Med<\/a> by U.S. National Library of Medicine<\/a> in the public domain<\/a>. ↵<\/a><\/li>
  4. This work is a derivative of Daily Med<\/a> by U.S. National Library of Medicine<\/a> in the public domain<\/a>. ↵<\/a><\/li><\/ol><\/div>","protected":false},"author":2,"menu_order":5,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":"cc-by"},"chapter-type":[49],"contributor":[],"license":[53],"class_list":["post-374","chapter","type-chapter","status-publish","hentry","chapter-type-numberless","license-cc-by"],"part":356,"_links":{"self":[{"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/pressbooks\/v2\/chapters\/374","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/wp\/v2\/users\/2"}],"version-history":[{"count":1,"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/pressbooks\/v2\/chapters\/374\/revisions"}],"predecessor-version":[{"id":375,"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/pressbooks\/v2\/chapters\/374\/revisions\/375"}],"part":[{"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/pressbooks\/v2\/parts\/356"}],"metadata":[{"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/pressbooks\/v2\/chapters\/374\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/wp\/v2\/media?parent=374"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/pressbooks\/v2\/chapter-type?post=374"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/wp\/v2\/contributor?post=374"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/pressbooks.publishdot.com\/nursingpharmacology\/wp-json\/wp\/v2\/license?post=374"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}