Straight dumpin
An 82-year-old male nursing home resident is sent to the emergency department with crampy lower abdominal pain and bloody diarrhea. On examination he has mild abdominal tenderness and slightly decreased bowel sounds. He has a previous history of vascular dementia, peripheral artery disease, hypertension, and hyperlipidemia. On examination he is afebrile, and a nasogastric aspirate is negative for evidence of bleeding.
Which one of the following is the most likely cause of this patient’s bleeding?
A) Peptic ulcer disease
B) Ischemic colitis
C) Diverticular bleeding
D) Angiodysplasia
E) Infectious colitis
ANSWER: B
This patient most likely has ischemic colitis, given his abdominal pain, bloody diarrhea, and cardiovascular risk factors. Peptic ulcer disease is unlikely because the nasogastric aspirate was negative. Diverticular bleeding and angiodysplasia are painless. Infectious colitis is associated with fever.
A healthy 83-year-old female presents for an annual Medicare visit. Her blood pressure is 165/95 mm Hg on initial evaluation today and 160/92 mm Hg on repeat measurement. She has no health complaints.
The JNC 8 panel recommends which one of the following as the goal blood pressure for this patient?
A) <135/85 mm Hg
B) <140/90 mm Hg
C) <150/90 mm Hg
D) <160/90 mm Hg
E) <160/100 mm Hg
ANSWER: C
In general, all patients with hypertension, regardless of age, benefit from treatment. Patients 80 years of age who are healthy and functionally independent should be treated according to current recommendations for patients >65 years old. Available guidelines recommend a target blood pressure of <150/90 mm Hg unless the patient is frail or has numerous comorbidities. In these cases, the target blood pressure should be determined on a case-by-case basis (SOR B).
Which one of the following has been shown to result from the use of continuous prophylactic antibiotics in patients with moderate COPD?
A) A clinically significant reduction in COPD exacerbations
B) A clinically significant improvement in quality-of-life scores
C) A demonstrable decrease in the number of resistant organisms in the sputum
D) The development of conduction defects, including prolonged QT intervals
E) An increased incidence of tinnitus
ANSWER: A
A review of multiple studies has revealed that continuous daily macrolide antibiotic use for 1 year decreased the number of exacerbations in older patients with COPD (SOR A). Quality of life did not show improvement, however, and resistance to macrolide and quinolone antibiotics rose. There was no increase in conduction abnormalities or tinnitus, but the incidence of hearing loss increased with the use of azithromycin.
The American Academy of Pediatrics recommends administration of an autism-specific screening tool at which well child visits?
A) 18 and 24 months
B) 2 and 3 years
C) 3 and 5 years
D) 5 and 10 years
E) 10 and 12 years
ANSWER: A
Since early intensive behavioral therapy can improve functional outcomes for children with autism and autism spectrum disorders, early diagnosis is critical. The American Academy of Pediatrics recommends screening all children with an autism-specific screening instrument at 18 and 24 months in addition to surveillance of developmental issues at all well child visits.
Which one of the following classes of medications for the treatment of diabetes mellitus is most likely to lead to weight loss?
A) GLP-1 receptor agonists such as exenatide (Byetta)
B) Meglitinides such as repaglinide (Prandin)
C) Sulfonylureas such as glipizide (Glucotrol)
D) Thiazolidinediones such as pioglitazone (Actos)
E) Insulin
ANSWER: A
GLP-1 receptor agonists are the most likely of these medications to lead to weight loss. They work by activating the GLP-1 receptors, which increases insulin secretion, decreases glucagon secretion, slows gastric emptying, and increases satiety. Other diabetes medications that may promote weight loss include metformin, amylin mimetics, and SGLT-2 inhibitors. The other medications listed have all been shown to cause weight gain. DPP-4 inhibitors are felt to be weight neutral.
A 55-year-old female with hypertension sees you for a routine follow-up visit. A physical examination is normal except for a BMI of 34.0 kg/m2. Laboratory findings are notable for an ALT (SGPT) of 53 U/L (N 7–35), and an AST (SGOT) of 28 U/L (N 10–34). She had a similar elevation a month ago when she was seen in the emergency department. Her comprehensive metabolic panel is otherwise normal, and a CBC is also normal. She has had negative hepatitis B surface antigen and hepatitis C antibody testing in the past. She does not drink alcohol or take medications that affect liver function.
Which one of the following is the most appropriate test for evaluating this patient?
A) Anti–smooth muscle antibody
B) Ceruloplasmin
C) Hepatitis D antibody
D) Iron studies
E) A liver biopsy
ANSWER: D
This patient is obese and has an isolated elevation of ALT. The initial history and workup, including testing for chronic hepatitis, a medication review, and alcohol screening, have all been conducted. Current guidelines suggest iron studies to screen for hemochromatosis as part of the initial evaluation (SOR C).
Anti–smooth-muscle antibody and ceruloplasmin levels can detect more rare causes of hepatocyte inflammation (autoimmune hepatitis and copper deposition from Wilson’s disease). These tests can be considered in persistent transaminitis based on clinical judgment (SOR C). Hepatitis D is a superinfection seen in patients with hepatitis B, and is not a consideration in this patient. A liver biopsy may also be considered in persistent transaminitis, especially in the setting of clinical or serologic evidence of advanced liver fibrosis, but is not recommended at this stage (SOR C). Patients with fatty liver disease are at increased risk for developing liver cirrhosis.
A 64-year-old male with nonvalvular atrial fibrillation has received anticoagulation therapy with warfarin (Coumadin) for the past 3 years but it has been difficult to maintain his INR in the therapeutic range. He has been afraid to transition to one of the newer oral anticoagulants because of the lack of a reversal medication should he develop life-threatening bleeding.
Which one of the following now has a reversal agent?
A) Apixaban (Eliquis)
B) Dabigatran (Pradaxa)
C) Edoxaban (Savaysa)
D) Rivaroxaban (Xarelto)
ANSWER: B
Idarucizumab has been approved for the urgent reversal of the anticoagulant effect of dabigatran. The dose is two consecutive 2.5-g infusions and the cost is $3500. Apixaban, edoxaban, and rivaroxaban—all factor Xa inhibitors—are not affected by this medication and they do not currently have a reversal agent.
A 70-year-old male has a smoking history of >30 pack-years. He quit 10 years ago.
Which one of the following is recommended by the U.S. Preventive Services Task Force with regard to lung cancer screening for this patient?
A) Low-dose noncontrast chest CT one time only
B) A standard chest radiograph and sputum cytology one time only
C) Low-dose noncontrast chest CT annually
D) Low-dose noncontrast chest CT every 3 years
E) No screening
ANSWER: C
The 2013 U.S. Preventive Services Task Force guidelines recommend annual lung cancer screening with low-dose CT for asymptomatic adults 55–80 years of age who have a 30-pack-year smoking history and currently smoke or have quit smoking within the past 15 years (grade B recommendation). Screening should be discontinued when the patient has not smoked for 15 years or develops a health problem that substantially limits life expectancy or the ability or willingness to have curative lung surgery.
A 6-year-old male is brought to an urgent care center with a 48-hour history of left hip pain.
He is noted to have a significant limp, but will walk. His father reports that the child prefers to lie on his back with his bent left knee out to the side. He is afebrile and well appearing, with an erythrocyte sedimentation rate of 10 mm/hr (N 3–13), a peripheral WBC count of 7000/mm3 (N 5000–10,000), and a C-reactive protein level of 6 mg/L (N <10). Radiographs of the left hip and knee are unremarkable.
Which one of the following would be most appropriate at this time?
A) Ibuprofen
B) Acetaminophen/codeine
C) Vancomycin
D) Physical therapy referral
E) Urgent orthopedic consultation
ANSWER: A
This child most likely has transient synovitis, based on the fact that he is well appearing and afebrile, and his WBC count, erythrocyte sedimentation rate, C-reactive protein level, and radiographs are all normal.
This is a self-limited inflammatory condition, and he will likely respond to NSAIDs such as ibuprofen and relative rest. Physical therapy and orthopedic consultation are not required, as this condition lasts less than a week. Septic arthritis would require treatment with intravenous antibiotics, but there is no evidence that he has this condition.
A 55-year-old male is found to be in cardiac arrest. When the EMTs arrive they note ventricular fibrillation on the monitor. The patient began an antibiotic 3 days ago for a mild case of community-acquired pneumonia.
Which one of the following antibiotics is most commonly associated with this scenario?
A) Doxycycline
B) Amoxicillin
C) Cefuroxime (Ceftin)
D) Azithromycin (Zithromax)
ANSWER: D
The likelihood of azithromycin inducing an arrhythmia is small, but given its widespread use this possibility must be kept in mind. The arrhythmia results from prolongation of the QT interval and is also more common in patients with a prior cardiac history. The other three antibiotics have not been implicated in an increase in cardiac deaths.
A 65-year-old male has severe liver cirrhosis from a combination of hepatitis C infection and alcohol abuse. He previously underwent a transjugular intrahepatic portosystemic shunt (TIPS) procedure.
While the TIPS procedure reduces the likelihood of most complications of cirrhosis, it may increase the risk for which one of the following?
A) Anasarca
B) Ascites
C) Hepatic encephalopathy
D) Upper gastrointestinal bleeding from esophageal varices
E) Upper gastrointestinal bleeding from portal hypertensive gastropathy
ANSWER: C
The transjugular intrahepatic portosystemic shunt (TIPS) procedure, by shunting blood destined for the liver into the systemic circulation, lowers pressure in the portal veins, thereby decreasing portal system hypertension and making variceal bleeding and portal hypertensive gastropathy less likely. TIPS may decrease the likelihood of variceal bleeding by as much as 90%. TIPS also reduces the pressure that leads to ascites and lower extremity edema, or the massive edema of anasarca. The diversion of blood from the liver circulation compromises the liver’s role in removing toxins, including the serum marker ammonia.
This may make patients more vulnerable to episodes of hepatic encephalopathy.
A 56-year-old male is hospitalized for workup of a syncopal episode. He has a history of type 2 diabetes mellitus and dyslipidemia, which are well controlled with metformin (Glucophage) and atorvastatin (Lipitor). In addition, he takes a daily low-dose aspirin and a multivitamin.
The cardiac examination reveals occasional skipped beats but the remainder of the physical examination is normal. While hospitalized he has another syncopal episode. His clinical
examination and EKG post syncope are normal. A telemetry rhythm tracing captured during this syncopal episode is shown on the page at right.
Which one of the following is the most likely cause of his syncope?
A) Atrial fibrillation
B) Mobitz type I second degree atrioventricular block
C) Mobitz type II second degree atrioventricular block
D) Third degree atrioventricular block
ANSWER: D
Third degree atrioventricular (AV) block is characterized by the inability of atrial impulses to reach the ventricles. Hence, the EKG will show both atrial activity (P waves) and ventricular “escape” activity (QRS complexes) with no correlation between them. Hemodynamically unstable patients with third degree AV block should be emergently treated with atropine and temporary pacing. With Mobitz type I AV block there is progressive PR interval prolongation preceding a nonconducted P wave. With Mobitz type II AV block the PR interval remains the same but there is a sudden dropped P wave. Second and third degree AV blocks are seen in patients with advanced heart disease. The EKG in atrial fibrillation lacks distinct P waves.
Additionally, fibrillary waves and irregularly irregular intervals between QRS complexes are characteristic (SOR C).
A 66-year-old female with a history of shortness of breath returns to your office to review her pulmonary function test results. Her FEV1/FVC ratio is 76%. You calculate that her FVC is below the normal range for an adult. Her DLCO is also low.
Which one of the following is most consistent with her pulmonary function test results?
A) COPD
B) Asthma
C) Idiopathic pulmonary fibrosis
D) Chronic pulmonary emboli
E) Morbid obesity
ANSWER: C
This patient’s pulmonary function test (PFT) findings are consistent with a restrictive defect with a low DLCO. Idiopathic pulmonary fibrosis, asbestosis, hypersensitivity pneumonitis, and sarcoidosis are restrictive lung diseases with a low diffusion capacity due to alveolar damage. COPD and asthma are both obstructive lung diseases, but can be associated with an abnormal DLCO. Morbid obesity causes a restrictive lung disease associated with a normal DLCO. The presence of chronic pulmonary emboli is associated with a low DLCO due to pulmonary vascular disease, but PFTs are normal.
The mother of a 16-year-old male calls to report that her son has a severe sore throat and has been running a fever of 102°F. As you question the mother further, which one of the following would be most specific for peritonsillar abscess?
A) A 1-day duration of illness
B) Ear pain
C) Difficulty opening his mouth
D) Hoarseness
E) Pain with swallowing
ANSWER: C
Trismus is almost universally present with peritonsillar abscess, while voice changes, otalgia, and odynophagia may or may not be present. Pharyngotonsillitis and peritonsillar cellulitis may also be associated with these complaints. Otalgia is common with peritonsillar abscess, otitis media, temporomandibular joint disorders, and a variety of other conditions. Peritonsillar abscess is rarely found in patients who do not have at least a 3-day history of progressive sore throat.
Supraventricular tachycardia may require treatment both acutely and over the long term.
Which one of the following medications is useful for both of these purposes?
A) Adenosine (Adenocard)
B) Amiodarone (Cordarone)
C) Esmolol (Brevibloc)
D) Procainamide
E) Verapamil (Calan, Verelan)
ANSWER: E
Calcium channel blockers such as verapamil or diltiazem can be used acutely to decrease heart rate and terminate supraventricular tachycardia (SVT) and chronically to prevent SVT recurrence. Adenosine, amiodarone, esmolol, and procainamide all can be used to treat SVT acutely, but they are not suitable for long-term therapy.
A 40-year-old male presents to the emergency department with a fever and acute, severe abdominal pain. A complete history and careful physical examination fail to localize the source of his pain, and basic blood and urine tests also prove to be nondiagnostic. His pain is diffuse, and you are concerned about a potentially serious pathology.
Which one of the following would be most appropriate to order next?
A) Plain radiographs of the abdomen
B) An upper gastrointestinal series with small-bowel follow-through
C) Ultrasonography of the abdomen
D) CT of the abdomen and pelvis
E) MRI of the abdomen
ANSWER: D
The differential diagnosis of acute nonlocalized abdominal pain is broad. CT is typically the imaging modality of choice if there is significant concern about serious pathology or if the diagnosis is unclear from the history, physical examination, and laboratory testing. In this instance, the American College of
Radiology recommends CT of the abdomen and pelvis, preferably with contrast. One prospective study of patients with nontraumatic abdominal pain in an emergency department setting found that CT results changed the leading diagnosis in 49% of patients and the management plan in 42% of patients.
A 30-year-old male is diagnosed with Lyme disease and is concerned because he read that this can lead to heart disease. Which one of the following is the most common cardiac problem associated with this disease?
A) Endocarditis
B) Heart block
C) Pericardial effusion
D) Pulmonary edema
E) Valvular heart disease
ANSWER: B
The most common cardiac abnormality associated with Lyme disease is fluctuating degrees of atrioventricular (AV) block. This may be first degree, second degree, or complete heart block. The condition is usually temporary, lasting from 3 to 42 days, with more advanced block lasting longer than
first degree AV block. The degree of AV block can fluctuate within minutes. The highest risk of AV block is in patients with a PR interval >300 msec. Other cardiac abnormalities such as myocarditis, left ventricular failure, and pericarditis are less common.
A 13-year-old female has been having difficulty breathing while playing soccer for the last few weeks. She has no personal or family history of asthma and has never needed medical treatments for breathing problems before. Her symptoms include coughing and wheezing only when running intensely for long periods of time. These symptoms persist for up to an hour after she stops exercising. She has no symptoms at other times during the day or at night. A pulmonary function test shows better than average lung function with no change after albuterol (Proventil, Ventolin) inhalation.
Which one of the following treatments would be a good first choice to help with this patient’s
symptoms?
A) A 5-day burst of oral prednisone
B) Daily use of a cromolyn inhaler
C) Daily inhaled corticosteroids during soccer season
D) An albuterol inhaler 10–15 minutes prior to exercise
E) Inhaled salmeterol (Serevent Diskus) every morning during soccer season
ANSWER: D
Asthmatic symptoms during exercise are common. These can occur as exacerbations of underlying airway inflammation or as bronchospasm in otherwise normal airways. This patient seems to have bronchospasm that would be best managed by albuterol prior to exercise. If she finds that she needs her inhaler frequently, the addition of an anti-inflammatory agent such as inhaled corticosteroids or oral montelukast would be reasonable.
A 14-year-old goalkeeper dives for a save during a soccer game and strikes her head on the goalpost. She does not lose consciousness but develops a headache and is removed by the coach for the remainder of the game. She becomes nauseated and has balance problems over the next several hours but can clearly recall the event. She comes to your clinic the following day. Her school requires baseline neurocognitive testing prior to all sports participation each year and you have a copy of this year’s results.
Which one of the following would be the most appropriate recommendation at this time?
A) CT of the head
B) Return to practice when her symptoms are relieved by medication
C) Neurocognitive testing at this visit
D) Physical and cognitive rest
E) The use of protective headgear for the remainder of the season
ANSWER: D
There are estimated to be 1.6–3.8 million sports-related concussions each year in the United States, and appropriate management can prevent many of the long-term complications. In this scenario, the patient meets the criteria for a concussion, with headache, nausea, and imbalance following an injury. She was appropriately removed from the game. The next step in management is complete physical and cognitive rest until her symptoms resolve without medication (SOR C). Complete physical rest includes avoidance of any physical activity that exacerbates symptoms. Cognitive rest means avoidance of activities that require concentration or attention, such as schoolwork and electronics use.
Once the patient’s symptoms have resolved without medication, she should be reevaluated and can start a graded return-to-play protocol (SOR C). Reevaluation may include repeat neurocognitive testing and postural stability testing (SOR C). Both types of testing can be important in the evaluation but there is insufficient evidence that either affects outcomes.
In the initial evaluation of concussion, imaging is not indicated in the absence of focal neurologic findings, loss of consciousness for more than 60 seconds, or evidence of skull fracture (SOR C). If imaging criteria are met, CT of the head is indicated. Plain films are not indicated in the evaluation.
There is no evidence that protective gear reduces the incidence of concussion (SOR C). Even though some protective gear can prevent other types of injuries, it is not indicated for concussion prevention. Eliminating dangerous behaviors such as heading the ball in soccer can help, however.
A 45-year-old female with a BMI of 50.0 kg/m2 comes to your office to discuss treatment of her chronically elevated fasting glucose levels. Recent test results include a hemoglobin A1c of 6.0%. In the past she was not able to tolerate metformin (Glucophage) and would like to try another medication to reduce her risk of developing diabetes mellitus.
Which one of the following medications would be most appropriate for this patient?
A) Acarbose (Precose)
B) Bromocriptine (Parlodel)
C) Canagliflozin (Invokana)
D) Glipizide (Glucotrol)
E) Sitagliptin (Januvia)
ANSWER: A
Individuals with impaired fasting glucose or impaired glucose tolerance have a higher risk of developing diabetes mellitus in the future. Randomized, controlled trials have shown that taking metformin,"-glucosidase inhibitors (acarbose), orlistat, or thiazolidinediones significantly reduces the risk of developing diabetes mellitus. The U.S. Diabetes Prevention Program Outcomes Study demonstrated a 34% reduction in the development of diabetes mellitus at 10 years. In addition to medications, it is also recommended that patients be counseled about weight loss and engaging in moderate physical activity for at least 150 minutes per week. The other medications listed are indicated for the treatment of diabetes but have not been shown to be effective for prevention.
A 56-year-old male with daily heartburn symptoms is found to have Barrett’s esophagus on endoscopy. Biopsies do not show any evidence of dysplasia.
Which one of the following should be recommended for surveillance of this condition?
A) Endoscopy every year
B) Endoscopy every 3 years
C) Endoscopy every 10 years
D) A PET scan every 2 years
E) No routine surveillance, with endoscopy only if symptoms worsen
ANSWER: B
Endoscopic screening results in the detection of Barrett’s esophagus in 6%–12% of patients with prolonged gastroesophageal reflux disease symptoms. Barrett’s esophagus, in which specialized intestinal columnar epithelium replaces the normal esophageal lining in response to chronic inflammation, is a precursor of
esophageal adenocarcinoma. The annual cancer risk for patients with nondysplastic Barrett’s esophagus is
0.12%–0.4%, with a significant increase in risk if dysplasia is present. Surveillance with endoscopy every 3 years is recommended for patients with Barrett’s esophagus without dysplasia. Patients with adenocarcinoma of the esophagus found during surveillance endoscopy are more likely to have early-stage, curable cancer than those whose cancer is found during a diagnostic endoscopy for evaluation of symptoms.
A 64-year-old female with a history of controlled hypertension reports that her older sister was recently hospitalized for a stroke. The patient feels well and has never had stroke symptoms. She requests your advice regarding carotid artery screening for stroke risk reduction.
Which one of the following would you recommend?
A) Carotid artery ultrasonography only if she has two or more cardiovascular risk
factors
B) Carotid artery ultrasonography once between the ages of 65 and 75 if she is a former smoker
C) Carotid artery ultrasonography once at age 65
D) Carotid artery auscultation annually after age 65
E) No screening for carotid artery disease
ANSWER: E
The U.S. Preventive Services Task Force recommends against screening for asymptomatic carotid artery stenosis (grade D recommendation), citing with moderate certainty that risks outweigh benefits. Although carotid artery stenosis is a risk factor for stroke, which is a major cause of death and disability, screening tests were not found to improve patient outcomes.
Asymptomatic carotid artery stenosis has a low prevalence (0.5%–1%) and carotid ultrasonography has a high rate of false-positives, exposing patients to harm from unnecessary treatment. Surgical treatments for carotid artery stenosis have a 30-day risk of stroke and mortality of 2.2%–3.8%. Carotid auscultation has not been found to be accurate or beneficial, and screening has not been shown to help optimize medical therapy.
Which one of the following does the 2014 Global Initiative for Chronic Obstructive Lung Disease (GOLD) guideline recommend for the treatment of exacerbations of COPD?
A) Prednisone, 40 mg daily for 5 days
B) Prednisone, 40 mg daily for 10 days
C) A methylprednisolone (Medrol) dose pack
D) Methylprednisolone sodium succinate (Solu-Medrol), 100 mg intravenously, followed by prednisone, 40 mg for 7 days
ANSWER: A
The 2014 Global Initiative for Chronic Obstructive Lung Disease (GOLD) guideline recommends administration of prednisone, 40 mg daily for 5 days, for COPD exacerbations. The 2011 GOLD guideline had recommended the same dosage of prednisone for 10–14 days. The guideline does not recommend a
methylprednisolone dose pack or intravenous methylprednisolone sodium succinate. A recent multicenter study showed that the shorter duration of low-dose prednisone was equivalent to the longer treatment.
Corticosteroids are associated with elevated blood glucose; the development of cataracts, diabetes mellitus, and osteopenia; and thromboembolic complications.
A school nurse calls you for recommendations about a healthy 6-year-old female who was
found to have head lice yesterday and was treated with permethrin 1% shampoo last night.
The nurse reports that on examination today the child appeared well, weighed 30 kg (66 lb),and had 6 nits on her scalp.
In addition to home eradication measures and regular nit combing, you recommend which one of the following for this child?
A) Oral ivermectin (Stromectol) and return to class today
B) Topical lindane and return to class today
C) Topical benzyl alcohol (Ulesfia) and return to class as soon as she is nit free
D) Return to class today and retreatment with permethrin 1% shampoo in 6 days
E) Retreatment with permethrin 1% shampoo in 6 days and return to class as soon as she is nit free
ANSWER: D
Family physicians are frequently consulted by patients and institutions regarding outbreaks of head lice.
Optimal treatment involves home eradication measures and medication. Permethrin 1% shampoo remains the first-line treatment. Ivermectin appears effective for treatment but is not FDA approved and is not considered first-line treatment. Lindane carries an increased risk of toxicity and should not be used in children weighing <50 kg. Topical benzyl alcohol is FDA-approved for treatment but is expensive. The current recommendation from the American Academy of Pediatrics Council on School Health and Committee on Infectious Diseases is to return children to class despite the presence of nits.
A 33-year-old patient with allergic rhinitis tells you he feels drowsy when taking diphenhydramine (Benadryl) and asks if there is an alternative that will cause less sedation. You tell him that most second-generation antihistamines have a better adverse effect profile and cause less sedation than first-generation antihistamines.
Which one of the following second-generation antihistamines would you advise the patient to avoid, however, because it is known to cause sedation?
A) Cetirizine (Zyrtec)
B) Desloratadine (Clarinex)
C) Fexofenadine (Allegra)
D) Levocetirizine (Xyzal)
E) Loratadine (Claritin)
ANSWER: A
Desloratadine, fexofenadine, levocetirizine, and loratadine are among the second-generation antihistamines that have a better adverse effect profile and cause less sedation than first-generation antihistamines (SOR A). Second-generation antihistamines have more complex chemical structures that decrease their movement across the blood-brain barrier, reducing central nervous system adverse effects such as sedation. Although cetirizine is generally classified as a second-generation antihistamine and a more potent histamine antagonist, it is known to cause sedation (SOR A).