Pharma Ch36 Antihistamine and related drug theraoy

Which instructions would the nurse include when teaching a patient about the use of a first-generation antihistamine? Select all that apply. Take prophylactically to ensure efficacy. Administer on an empty stomach to enhance absorption. Avoid alcohol while taking the antihistamine because of the risk for central nervous system (CNS) depression. Sugarless candy and frequent sipping of liquids can help with dry mouth from the antihistamine. Avoid tasks requiring mental alertness, such as driving, until the patient determines the drug is not affecting motor skills or responses.

Take prophylactically to ensure efficacy. Antihistamines are best taken prophylactically and are less effective in the presence of acute symptoms. Avoid alcohol while taking the antihistamine because of the risk for central nervous system (CNS) depression. Alcohol and other CNS depressants should be avoided in patients receiving first-generation antihistamines because of the risk for additive CNS depression. Sugarless candy and frequent sipping of liquids can help with dry mouth from the antihistamine. Sugarless candies and frequent sipping of liquids can help combat dry mouth that is associated with first-generation antihistamines. Avoid tasks requiring mental alertness, such as driving, until the patient determines the drug is not affecting motor skills or responses. Patients should avoid tasks requiring mental alertness, such as driving, until the patient is able to determine the drug has not significantly affected his or her motor skills or responses or until tolerance develops.

n which time frame would the nurse expect to see an improvement in a patient's allergic symptoms after the administration of diphenhydramine? 5 to 10 minutes 15 to 30 minutes 30 to 60 minutes 60 to 120 minutes

15 to 30 minutes Diphenhydramine's onset of action is 15 to 30 minutes. This is when a patient would likely notice some improvement in allergic symptoms.

Which instructions and action step would the nurse include when teaching Ms. Stevens about the administration of diphenhydramine? Avoid taking diphenhydramine with the narcotic because of sedation. Call her health care provider to discuss changing her narcotic to another nonsedating pain medication. Avoid taking diphenhydramine with the narcotic because of overstimulation. Call her health care provider to discuss changing her narcotic to another pain medication. Take diphenhydramine at the onset of allergic symptoms for best effects. The drug should be administered with food for best effects. Take diphenhydramine at the onset of allergic symptoms for best effects. The drug should be administered without food for best effects.

Avoid taking diphenhydramine with the narcotic because of sedation. Call her health care provider to discuss changing her narcotic to another nonsedating pain medication. Taking diphenhydramine with a narcotic can result in additive central nervous system (CNS) depression, particularly causing significant drowsiness. Therefore Ms. Stevens should avoid this combination and seek a nonsedating pain medication from her health care provider. Alternatively, she can also call her health care provider to discuss the use of a nonsedating antihistamine.

Which antihistamine is associated with significant sedation? Cetirizine Chlorpheniramine Fexofenadine Loratadine

Chlorpheniramine Chlorpheniramine is considered a first-generation antihistamine that is associated with significant sedation.

Which antihistamines are associated with minimal to no sedation? Select all that apply. Brompheniramine Desloratadine Diphenhydramine Hydroxyzine Levocetirizine

Desloratadine Desloratadine is considered a second-generation antihistamine that is associated with minimal to no sedation. Levocetirizine Levocetirizine is considered a second-generation antihistamine that is associated with minimal to no sedation.

Which side effects would the nurse monitor for in a patient receiving an initial dose of diphenhydramine? Select all that apply. Dizziness Dry mouth Restlessness Sedation Tremors Visual changes

Dizziness Dizziness is a common side effect associated with first-generation antihistamines like diphenhydramine. Dry mouth Dry mouth is an anticholinergic side effect associated with first-generation antihistamines like diphenhydramine. Sedation Sedation or drowsiness is a common side effect associated with first-generation antihistamines like diphenhydramine. Visual changes Visual changes are an anticholinergic side effect associated with first-generation antihistamines like diphenhydramine.

Which effects resulting from stimulation of H1 receptors are blocked by antihistamines? Select all that apply. Edema Flushed skin Itching Mucosal secretions Gastric secretions

Edema Flushed skin Itching Mucosal secretions

Which clinical manifestation alerts a nurse to a possible drug interaction in a patient who is receiving both diazepam and diphenhydramine? Edema/weight gain Excessive drowsiness/lethargy Excessive sweating/heat intolerance Palpitations/overstimulation

Excessive drowsiness/lethargy Diazepam is a benzodiazepine that causes central nervous system (CNS) depression. Because first-generation antihistamines can also cause significant CNS depression, the combination of these drugs can cause additive CNS depression resulting in excessive drowsiness and lethargy. The dosage of the diazepam may need to be decreased while the patient is receiving diphenhydramine. Alternatively, the benzodiazepine or diphenhydramine may be altered to another drug that does not cause significant sedation.

Which patients should avoid taking antihistamines unless discussed with a health care provider? Select all that apply. Older adult Newborn infant Breastfeeding female Patient with dyslipidemia Patient with anxiety Patient with type 2 diabetes

Older adult First-generation antihistamines should be avoided in older adults because they are prone to the anticholinergic effects and are at risk for falls. Newborn infant Newborn infants should not receive first-generation antihistamines because of safety concerns. Breastfeeding female Breastfeeding women should avoid first-generation antihistamines because there is a risk for overly sedating the nursing infant.

Which statements describe the pharmacokinetics of diphenhydramine? Select all that apply. Oral administration is associated with good absorption in the gastrointestinal tract. When used topically, there is minimal systemic absorption of diphenhydramine. The drug is 80% to 85% protein bound. Diphenhydramine undergoes hepatic metabolism. The drug is excreted in the feces.

Oral administration is associated with good absorption in the gastrointestinal tract. Diphenhydramine is well absorbed in the gastrointestinal tract after oral administration. When used topically, there is minimal systemic absorption of diphenhydramine. Topical administration of diphenhydramine is not expected to be systemically absorbed to any significant degree. The drug is 80% to 85% protein bound. Diphenhydramine is 80% to 85% protein bound. Diphenhydramine undergoes hepatic metabolism. The drug is metabolized by the liver.

Which baseline assessment parameters would be obtained by a nurse before administration of an antihistamine to a patient? Select all that apply. Patient age Medication history Blood glucose levels Complete blood count Pulmonary function tests

Patient age Determining the patient's age is important to determine if the patient can safely receive therapy with an antihistamine. Older adults should avoid treatment with first-generation antihistamines because of a risk for falls. Newborn infants cannot receive antihistamines because of safety concerns. Medication history Determining the patient's medication history is important for a nurse to screen for potential drug-drug interactions before initiation with an antihistamine.

Which statement regarding the pharmacokinetics of loratadine is accurate? Loratadine is slowly absorbed after administration. The drug is minimally protein bound. Loratadine's metabolism predominantly occurs through CYP1A2. The drug is largely and equally excreted in urine and feces.

The drug is largely and equally excreted in urine and feces. It is true that approximately 80% of loratadine is excreted equally in urine and feces.

Which statement about the pharmacodynamics of loratadine is accurate? The drug's effects typically last for 1 day. Loratadine reaches its peak effects in 1 to 3 hours. Loratadine readily crosses the blood-brain barrier, leading to significant sedation. Patients can expect the drug to begin working within 15 to 30 minutes of administration.

The drug's effects typically last for 1 day. Loratadine has a duration of action of 24 hours. It is typically dosed once daily.

Which statements describe the mechanism of action of antihistamines? Select all that apply. They bind to muscarinic and other nonhistaminic receptors. Antihistamines push out histamine that is bound to receptors. They block the release of histamine from mast cells and basophils. Antihistamines block histamine from binding to open H1 receptors on basophil and mast cell surfaces. The binding of antihistamines to H1 receptors prevents the negative effects caused by the binding of histamine.

They bind to muscarinic and other nonhistaminic receptors. Antihistamines bind to muscarinic and other nonhistaminic receptors, producing side effects. Antihistamines block histamine from binding to open H1 receptors on basophil and mast cell surfaces. Antihistamines exert their effects by preventing histamine from binding to open H1 receptors on the surfaces of basophils and mast cells. The binding of antihistamines to H1 receptors prevents the negative effects caused by the binding of histamine. Antihistamines prevent the negative effects caused by histamine binding to H1 receptors such as itching, production of mucosal secretions, edema, and flushed skin.