Category: Pharmacology & Therapeutics
Keywords: insulin, metformin, sulfonylureas, repaglinide (PubMed Search)
Posted: 7/4/2013 by Ellen Lemkin, MD, PharmD
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Diabetes. Pharmacist's Letter March 2013;29(3):13-4.
Category: Pharmacology & Therapeutics
Keywords: cellulitis, cephalexin, sulfamethoxazole/trimethoprim, Bactrim, streptococcus (PubMed Search)
Posted: 5/20/2013 by Bryan Hayes, PharmD
(Emailed: 6/1/2013)
(Updated: 5/31/2013)
Click here to contact Bryan Hayes, PharmD
Background
In the current era of community-acquired MRSA (CA-MRSA), most of our outpatient treatment options for cellulitis aim to cover MRSA. Choices include sulfamethoxazole/trimethoprim (SMZ-TMP), doxycycline, linezolid, and clindamycin (depending on local susceptibility patterns).
A New Study
Take Home Clinical Points
Pallin DJ, et al. Clinical Trial: Comparative Effectiveness of Cephalexin Plus Trimethoprim-Sulfamethoxazole Versus Cephalexin Alone for Treatment of Uncomplicated Cellulitis: A Randomized Controlled Trial. Clinical Infectious Diseases 2013;56(12):1754-62. [PMID 23457080]
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Category: Pharmacology & Therapeutics
Keywords: phosphate, fosphenytoin, phenytoin, hyperphosphatemia (PubMed Search)
Posted: 4/29/2013 by Bryan Hayes, PharmD
(Emailed: 5/4/2013)
(Updated: 5/2/2013)
Click here to contact Bryan Hayes, PharmD
Introduction
Fosphenytoin is a prodrug and is metabolized quickly to phenytoin after administration. The conversion of fosphenytoin to phenytoin involves the release of phosphate. In fact, each mmol of fosphenytoin releases 1 mmol of phosphate.
Clinical Question
Are patients at risk for hyperphosphatemia after fosphenytoin loading?
Data
There are only two cases of reported hyperphosphatemia.
Bottom Line
Despite the phosphate load from fosphenytoin administration, hyperphosphatemia is very rare and probably associated with renal insufficiency and dosing errors.
McBryde KD, et al. Hyperphosphatemia due to fosphenytoin in a pediatric ESRD patient. Pediatr Nephrol. 2005;20(8):1182-5. [PMID 15965770]
Rose R, et al. Fosphenytoin-induced bradyasystole arrest in an infant treated with charcoal hemofiltration [abstract]. J Toxicol Clin Toxicol. 1998;36:473.
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Category: Pharmacology & Therapeutics
Keywords: Prothrombin Complex Concentrate, warfarin, coumadin, vitamin K antagonist, anticoagulant, PCC (PubMed Search)
Posted: 5/2/2013 by Ellen Lemkin, MD, PharmD
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Approval of Kcentra™ may open the door for studying treatment of the bleeding patient on newer oral anticoagulants.
Category: Pharmacology & Therapeutics
Keywords: alteplase, tPA, dabigatran, anticoagulant, apixaban, rivaroxaban (PubMed Search)
Posted: 4/3/2013 by Bryan Hayes, PharmD
(Emailed: 4/6/2013)
(Updated: 4/5/2013)
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A new recommendation in the 2013 Ischemic Stroke Guidelines provides guidance on what to do in patients taking new oral anticoagulants who are deemed eligible for IV fibrinolysis. Here is what the guidelines say:
Until further data are available, a history consistent with recent use of new oral anticoagulants generally precludes use of IV tPA.
Jauch EC, et al. Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke 2013;44(3):870-947. PMID 23370205
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Category: Pharmacology & Therapeutics
Keywords: Status epilepticus, Keppra, seizures, valproic acid, levetiracetam (PubMed Search)
Posted: 4/4/2013 by Ellen Lemkin, MD, PharmD
(Updated: 3/28/2024)
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Trinka E. What is the evidence to use new intravenous AED in status epilepticus? Epilepsia 2011 52(Suppl 8):35-8.
Zelano J, Kumlien E. Levetiracetam as alternative stage two antiepileptic drug in status epilepticus: A systematic review. Seizure 2012. 21:233-6.
Category: Pharmacology & Therapeutics
Keywords: Statins, Acute Coronary Syndrome, Myocardial Infarction (PubMed Search)
Posted: 3/7/2013 by Ellen Lemkin, MD, PharmD
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Statins for acute coronary syndrome. Cochrane Database of Systemic Reviews. Volume 9, 2011.
Category: Pharmacology & Therapeutics
Keywords: ischemic stroke, hypertension, blood pressure (PubMed Search)
Posted: 2/25/2013 by Bryan Hayes, PharmD
(Emailed: 3/2/2013)
(Updated: 3/2/2013)
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The newest iteration of 'Guidelines for the Early Management of Patients with Acute Ischemic Stroke' was recently published. Here are the key revisions specific to blood pressure management:
If administering rtPA, blood pressure needs to be <185/110 mm Hg. That recommendation didn't change.
Jauch EC, et al. Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke 2013 Jan 31 [Epub ahead of print]. PMID 23370205.
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Category: Pharmacology & Therapeutics
Keywords: lidocaine, intraosseus, IO (PubMed Search)
Posted: 1/2/2013 by Bryan Hayes, PharmD
(Emailed: 2/2/2013)
(Updated: 2/2/2013)
Click here to contact Bryan Hayes, PharmD
Intraosseus (IO) access has become quite popular in critically ill patients requiring immediate resuscitation. In a patient responsive to pain, however, pain and discomfort is associated with the force of high-volume infusion through the established line.
Before flushing the line, consider administering preservative-free 2% lidocaine (without epinephrine) for patients responsive to pain prior to flush.
The suggested dose is 20-40 mg (1-2 mL) of the 2% lidocaine, followed by the 10 mL saline flush.
If preservative-free 2% lidocaine is not stocked in your ED, now is the time to consider adding it.
Fowler RL, Pierce, Nazeer S, et al. Powered intraosseous insertion provides safe and effective vascular access for emergency patients. Ann Emerg Med 2008;52(4):S152.
Ong MEH, Chan YH, Oh JJ, et al. An observational, prospective study comparing tibial and humeral intraosseus access using EZ-IO. Am J Emerg Med 2009;27(1):8-15. [PMID 19041528]
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Category: Pharmacology & Therapeutics
Keywords: Tdap, tetanus, immunization, vaccine, pertussis (PubMed Search)
Posted: 1/3/2013 by Bryan Hayes, PharmD
(Emailed: 1/5/2013)
(Updated: 1/5/2013)
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The two available Tetanus/reduced diphtheria toxoid/acellular pertussis (Tdap) vaccine products in the U.S. are Boostrix and Adacel. Neither were originally approved in older adults age 65 and older. Boostrix received FDA-approval for use in this age group in July 2011, but Adacel never has.
However, in June 2012 ACIP issued new guidance recommending Tdap for all adults age 65 years and older.
"When feasible, Boostrix should be used for adults aged 65 years and older; however, ACIP concluded that either vaccine administered to a person 65 years or older is immunogenic and would provide protection. A dose of either vaccine may be considered valid."
Bottom line: Regardless of which Tdap product is stocked at your institution, both are considered safe to use in adults 65 years and older.
Centers for Disease Control and Prevention (CDC), “Updated Recommendations for Use of Tetanus Toxoid, Reduced Diphtheria Toxoid, and Acellular Pertussis (Tdap) Vaccine in Adults Aged 65 Years and Older - Advisory Committee on Immunization Practices (ACIP)," MMWR Morb Mortal Wkly Rep, 2012, 61(25):468-70. [PMID 22739778]
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Category: Pharmacology & Therapeutics
Keywords: doxycycline, PID, pelvic inflammatory disease, STD, azithromycin (PubMed Search)
Posted: 11/28/2012 by Bryan Hayes, PharmD
(Emailed: 12/1/2012)
(Updated: 12/1/2012)
Click here to contact Bryan Hayes, PharmD
In the rare circumstance you need to treat a patient with suspected PID and an allergy to doxycycline, what is the alternative?
For oral regimens, azithromycin is an option in place of doxycycline.
Suggested regimen for PID with doxycycline allergy:
Bevan CD, Ridgway GL, Rothermel CD. Efficacy and safety of azithromycin as monotherapy or combined with metronidazole compared with two standard multidrug regimens for the treatment of acute pelvic inflammatory disease. J Int Med Res 2003;31:45–54.
Savaris RF, Teixeira LM, Torres TG, et al. Comparing ceftriaxone plus azithromycin or doxycycline for pelvic inflammatory disease: a randomized controlled trial. Obstet Gynecol 2007;110:53–60.
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Category: Pharmacology & Therapeutics
Keywords: penicillin, cross-reactivity, cephalosporin, IgE, allergy (PubMed Search)
Posted: 10/29/2012 by Bryan Hayes, PharmD
(Emailed: 11/3/2012)
(Updated: 11/3/2012)
Click here to contact Bryan Hayes, PharmD
It seems we've finally put to bed the myth that 10% of penicillin-allergic patients will also react to cephalosporins. Dr. Campagna, et al. recently published a review article concluding that the true cross-reactivity is negligible except when side-chains are similar [PMID 21742459].
This topic was also the subject of a recent post on the Academic Life in EM blog (http://academiclifeinem.blogspot.com/2012/08/busting-myth-10-cephalosporin.html).
But what about the reverse question? Can I give a penicillin to a cephalosporin-allergic patient?
Dr. Romano's group tested 98 patients with skin-test postitive cepahlosprin allergy (mostly IgE -mediated anaphylaxis). Patients were then skin tested for penicillin allergy. Those testing negative were challenged with a penicillin.
25% of patients reacted to the penicillin
Similar side-chain was a strong predictor of cross-reactivity
A Letter to the Editor response to this study pointed out that the authors used a smaller-than-standard size threshold for a positive response to the penicllin AND used a higher-than-standard dose of amoxicillin for testing. In light of this, the rate of subjects with cephalosporin allergy who do not have a history of penicillin allergy but with true IgE-mediated allergy to penicillin might be much closer to 5%.
Bottom line: The cross-reactivity of penicillins in cephalosporin-allergic patients is somewhere between 5-25%.
Romano A, et al. IgE-mediated hypersensitivity to cephalosporings: cross-reactivity and tolerability of penicillins, monobactams, and carbapenems. J Allergy Clin Immunol 2010;126(5):994-9.
Macy E. Penicillin allergy might not be very common in subjects with cephalosporin allergy. J Allergy Clin Immunol 2011;127(6):1638-9.
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Category: Pharmacology & Therapeutics
Keywords: ACE inhibitors, angioedema, icatibant (PubMed Search)
Posted: 11/1/2012 by Ellen Lemkin, MD, PharmD
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Category: Pharmacology & Therapeutics
Keywords: ACE inhibitors, angioedema, icatibant (PubMed Search)
Posted: 11/1/2012 by Ellen Lemkin, MD, PharmD
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Wilerson G. Angioedema in the Emergency Department: An evidence-based review. Emergency Medicine Practice, Nov 2012.
Category: Pharmacology & Therapeutics
Keywords: sulfa, allergy, cross-reactivity, antimicrobial, sulfonamide (PubMed Search)
Posted: 9/24/2012 by Bryan Hayes, PharmD
(Emailed: 10/6/2012)
(Updated: 10/6/2012)
Click here to contact Bryan Hayes, PharmD
Patients frequently report having a sulfa allergy. In most cases, the allergic reaction was secondary to a sulfonamide antimicrobial agent, such as sulfamethoxazole-trimethoprim.
The question is: Can I use furosemide (or other non-antimicrobial agents containing a sulfa component)?
There is minimal evidence of cross-reactivity between sulfonamide antimicrobials and non-antimicrobials.
Despite this, the U.S. FDA-approved product information for many non-antimicrobial sulfonamide drugs contains warnings concerning possible cross-reactions.
Bottom line: If a patient had a true IgE-mediated anaphylatic reaction to a sulfonamide antimicrobial, it may be best to avoid other sulfa-related medications (use ethacrynic acid if a loop diuretic is needed). Otherwise, the available literature does not support cross-reactivity between sulfonamide antimicrobials and non-antimicrobials.
Strom BL, et al. Absence of cross-reactivity between sulfonamide antibiotics and sulfonamide nonantibiotics. N Engl J Med 2003;349(17):1628-35.
Hemstreet BA, et al. Sulfonamide allergies and outcomes related to use of potentially cross-reactive drugs in hospitalized patients. Pharmacother 2006;26(4):551-7.
Lee AG, et al. Presumed "sulfa allergy" in patients with intracranial hypertension treated with acetazolamide or furosemide: cross-reactivity, myth or reality? Am J Ophthalmol 2004;138(1):114-8.
Johnson KK, et al. Sulfonamide cross-reactivity: fact or fiction? Ann Pharmacother 2005;39(2):290-301.
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Category: Pharmacology & Therapeutics
Keywords: carbapenem, penicillin, allergy, skin test, cross-reactivity (PubMed Search)
Posted: 8/26/2012 by Bryan Hayes, PharmD
(Emailed: 9/1/2012)
(Updated: 9/4/2013)
Click here to contact Bryan Hayes, PharmD
Carbapenems (meropenem, ertapenem, doripenem, imipenem/cilastatin) are broad-spectrum antibiotics that have good gram-negative and anaerobic coverage and are used to treat resistant bacterial infections.
Early retrospective studies showed ~10% cross-reactivity in penicillin-allergic patients.
More recent prospective studies verified penicillin allergy by the accepted standard (ie, skin test to the major and minor penicillin determinants) and tested for carbapenem allergy by administering a full therapeutic dose to carbapenem skin test-negative patients.
The cross-reactivity between skin tests appears to be around 1%, with all carbapenem skin test-negative patients tolerating the challenge.
Frumin J, Gallagher JC. Allergic cross-sensitivity between penicillin, carbapenem, and monobactam antibiotics: what are the chances? Ann Pharmacother 2009;43(2):304-15.
Herbert ME, Brewster GS, Lanctot-Herbert M. Medical myth: ten percent of patients who are allergic to penicillin will have serious reactions if exposed to cephalosporins. West J Med 2000;172:341.
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Category: Pharmacology & Therapeutics
Keywords: vasopressor, cardiac arrest, epinephrine, vasopression (PubMed Search)
Posted: 7/30/2012 by Bryan Hayes, PharmD
(Emailed: 8/4/2012)
(Updated: 8/4/2012)
Click here to contact Bryan Hayes, PharmD
A recent paper reviewed 53 articles to assess the utility of vasopressors in cardiac arrest. The authors aimed to determine if vasopressors improved ouctomes in this patient population. Here are their conclusions:
Although these conclusions don't support the use of vasopressors in cardiac arrest, we should not abandon these therapies. Most of the trials were completed before wide-spread recognition of the post-cardiac arrest syndrome, implementation of therapeutic hypothermia protocols, and early cardiac catheterization.
Larabee TM, Liu KY, Campbell JA, et al. Vasopressors in cardiac arrest: a systematic review. Resuscitation. 2012;83(8):932-9.
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Category: Pharmacology & Therapeutics
Keywords: Uti,bactrim,smx/tmp,ciprofloxacin,levofloxacin (PubMed Search)
Posted: 8/2/2012 by Ellen Lemkin, MD, PharmD
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Acute, uncomplicated cystitis (in the non-pregnant female):
· The drug of choice is SMX/TMP (provided the resistance rate is <20%) X 3 days.
· An alternative is nitrofurantoin X 5 days.
Acute, uncomplicated pyleonephritis (in the non-pregnanct female) may be treated with:
· Levofloxacin X 5 days, or ciprofloxacin X 7 days (provided resistance rate is <10%).
· Alternatively, SMX/TMP may be used X 14 days.
The Medical Letter. July 23, 2012. Vol 54(1395):57-60.
Category: Pharmacology & Therapeutics
Keywords: alteplase, tPA, warfarin, INR, ischemic stroke (PubMed Search)
Posted: 7/2/2012 by Bryan Hayes, PharmD
(Emailed: 7/7/2012)
(Updated: 7/7/2012)
Click here to contact Bryan Hayes, PharmD
Issue 1: Mean INR in study patients was only 1.22 (median 1.2). An INR of 1.2 represents very little actual anticoagulation.
Issue 2: In the small subgroup of patients with INR 1.5 to 1.7 (n = 269) there was a higher risk of ICH (7.8%), but did not reach statistical significance (it was significant in the unadjusted risk population).
Bottom line: Patients with INRs < 1.5 may be ok to receive tPA. Patients with INRs 1.5 or greater need further study.
Xian Y, Liang L, Smith EE, et al. Risk of Intracranial Hemorrhage Among Patients With Acute Ischemic Stroke Receiving Warfarin and Treated with Intravenous Tissue Plasminogen Activator. JAMA. 2012;307(24):2600-8.
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Category: Pharmacology & Therapeutics
Keywords: naltrexone, methylnaltrexone, constipation, opioid dependence (PubMed Search)
Posted: 6/1/2012 by Bryan Hayes, PharmD
(Emailed: 6/2/2012)
(Updated: 6/15/2012)
Click here to contact Bryan Hayes, PharmD
Naltrexone and methylnaltrexone are both mu-receptor antagonists that look similar and have similar names. But, they have very different uses.
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