ISSN: 2572-3308 Malone and Kennedy. Int J Aller Medications 2017, 3:024 DOI: 10.23937/2572-3308.1510024 Volume 3 | Issue 1 International Journal of Open Access Allergy Medications REVIEW ARTICLE Review: Side Effects of Some Commonly Used Allergy Medica- tions (Decongestants, Anti-Leukotriene Agents, Antihistamines, Steroids, and Zinc) and Their Safety in Pregnancy Michael Malone1* and Tara M Kennedy2 1Associate Professor and Medical Director, Department of Family and Community Medicine, Pennsylvania State University, USA 2Resident Physician, Department of Family and Community Medicine, Pennsylvania State University, USA *Corresponding author: Michael Malone, Associate Professor and Medical Director, Department of Family and Community Medicine, Pennsylvania State University, USA, E-mail: [email protected] Abstract Introduction Objective: The aim of this study was to evaluate the safety Allergic conditions are common, although most indi- and side-effects of common allergy medications. viduals with allergies do not seek medical care [1]. In the Methodology: A literature search was undertaken. We searched United States allergy medications are readily available the databases of Pubmed, MEDLINE, EMBASE databases, and over the counter. While most people will report relief of Cochrane Library from 1990 to October 2016, using key words: their symptoms with readily available allergy treatments, Allergy, Medications, Antihistamines, Decongestants, Montelu- approximately 7% of patients who take these medications kast, Side effects, Adverse Events, Adverse, Effects, Zinc, Ste- roids, Pregnancy, Reviews, RCT, and Case Report. will experience adverse effects (AEs), which can be severe [2]. This article will review side effects reported in the lit- Results: Antihistamines can cause undesired anti-cholinergic erature for some of the most common prescription and effects including mydraisais, sedation, dry eyes, dry mouth, con- stipation and urinary retention. Significant overdose of antihista- over-the-counter allergy medications. mines can cause serious toxicity and even death. Cetirizine or loratadine are preferred based on their good safety profile and Literature Review Results recommendation in multiple guidelines during pregnancy. Side Decongestants effects are more common with oral decongestants than with top- ical sprays. Decongestant side-effects include nausea, vomiting, Decongestants can be useful medications allergic rhi- insomnia, dizziness, elevated blood pressure, restlessness, anx- nitis with congestion. Particularly in the spring and winter iety, hallucinations, seizure, psychosis, headache, urinary dys- function, stroke, intracranial bleed, arrhythmias, and myocardial months many people use or misuse excessive doses of infarction. Anti-leukotriene agents, topical steroids, and intranasal decongestant agents to relieve allergic congestive symp- steroids are generally well tolerated. Intranasal zinc has been re- toms without a physicians’ prescription. Nasal deconges- ported to cause zinc-induced anosmia syndrome which is char- tants include the oral decongestants phenylephrine and acterized by nasal burning followed by anosmia and can be dis- pseudoephedrine, as well as topical sprays (Phenyleph- tinguished from post-viral anosmia based on history. rine, Oxymetazoline) and an inhaler Propylhexedrine. Conclusion: Although serious side-effects can occur, the ma- The majority of the agents used as decongestants stim- jority of the common allergy medications reviewed in this arti- cle was well-tolerated and had only rare serious side effects. ulates α-adrenergic receptors and reduce edematous mucosal tissue volume and mucus secretions by causing Keywords vasoconstriction of the upper respiratory tract, parana- Allergies, Allergy treatment, Side effects, Adverse events, sal sinuses, and nasal mucosa [3]. Decongestants are safe Adverse effects, Allergy medication, Steroids, Antihistamines, for many patients, but a significant number of side-ef- Decongestants, Anti-leukotriene agents fects have been reported. Adverse effects of deconges- Citation: Malone M, Kennedy TM (2017) Review: Side Effects of Some Commonly Used Allergy Medications (Decongestants, Anti-Leukotriene Agents, Antihistamines, Steroids, and Zinc) and Their Safety in Pregnancy. Int J Aller Medications 3:024. doi.org/10.23937/2572-3308.1510024 Received: October 30, 2016: Accepted: March 24, 2017: Published: March 27, 2017 Copyright: © 2017 Malone M, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Malone and Kennedy. Int J Aller Medications 2017, 3:024 • Page 1 of 6 • DOI: 10.23937/2572-3308.1510024 ISSN: 2572-3308 tants result from a direct effect on adrenergic receptors on therapy for asthma; however, they also have prov- and stimulation of the CNS. en efficacy and FDA approval for use in allergic rhinitis. Both oral and nasal decongestants are contraindicat- The Antileukotriene agents in the United States include ed for patients with heart disease, hypertension, thyroid montelukast and zafirulast which act by antagonizing disease, diabetes, and men with benign prostatic hyper- the leukotriene receptor, and zileuton which inhibits trophy. Nasal decongestants, however, appear to have leukotriene synthesis. In general, antileukotriene agents significantly less risk [4,5]. Decongestants should not be appear to be well tolerated. Drug metabolism occurs taken with Monoamine oxidase inhibitors as they can lead via the Cytochrome P450 system in liver, creating the to a life-threatening rise in blood pressure. Side effects are potential for interactions with other medications using more common with oral decongestants than with topical the P450 system; however, no such drug interactions sprays and include nausea, vomiting, insomnia, dizziness, have been reported to the FDA [15] Rare, but serious elevated blood pressure, restlessness, anxiety, hallucina- side effects of Montelukast have been reported. In 2009 tions, seizure, psychosis, headache, urinary dysfunction, the FDA mandated a label change for Montelukast af- stroke, intracranial bleed, arrhythmias, and myocardial in- ter reports of neuropsychiatric side effects [16]. Merck farction [3,6,7]. Although decongestants may lead to hyper listed reports of agitation, aggression, depression and excitability and an increased risk of seizure, a recent animal suicidality [17]. Despite the label change, multiple stud- study showed a paradoxical effect in which phenylephrine ies failed to find a definitive link between montelukast potentiates the anticonvulsant effect and neutralizes the and suicidality, which is why there was no black box sedative effect of diazepam in rats [8]. Rare serious side warning. A 2011 review article failed to find evidence of effects that have been reported in the literature include change in both the use of Montelukast and neuropsy- a case report of an otherwise healthy 37-year-old woman chiatric events after the label change [16]. who presented with acute-onset spinal artery vasospasm In a Japanese study on the use of montelukast for treat- resulting in quadriplegia after decongestant (ephedrine) ment of perennial allergic rhinitis, there were no serious use [9]. adverse effects and one discontinuation due to adverse Purposeful abuse: Nasal decongestants have sig- effects. The most common adverse effects in any of the nificant potential for abuse. Long-term use of decon- treatment groups were nasopharyngitis, pharyngitis, and gestant nasal spray (and occasionally with oral decon- acute sinusitis [18]. Montelukast-induced metamorphop- gestants) can cause rebound nasal congestion known sia, a type of visual distortion in which straight lines appear as rhinitis medicamentosa (RM). A review of 33 cases wavy or disappear, has also been reported in the literature of rhinitis medicamentosa showed only seven cases had [19]. duration of use less than one year and about half had Intranasal steroids duration of use more than two years [10]. In the review, approximately 2/3 of the cases of RM resulted from in- Intranasal steroids are considered first line therapy appropriate treatment of allergic rhinitis. The long du- to reduce inflammation, nasal congestion, and post-na- ration of use prior to the onset of RM is also consistent sal drip in allergic rhinitis and are many are now avail- with a recent Cochrane review noting that short-term able over-the-counter [20]. Intranasal steroids have use of nasal decongestants do not seem to increase the low bioavailability, alleviated most of the harmful side risk of adverse events in adults. The effectiveness and effects of systemic steroids. The second-generation safety of nasal decongestants in children is yet to be de- intranasal corticosteroid (INC) agents currently in use termined [11]. (mometasone, fluticasone, ciclesonide) further min- Fortunately, rhinitis medicamentosa with nasal con- imize systemic bioavailability (< 1%) compared with gestion appears readily reversible with suitable treatment older INCs and compared with oral agents and reduces [10]. Treatment of RM is immediate withdrawal, although the risk for systemic adverse events [21]. While concern adjuvant use of steroid nasal or oral corticosteroids during exists among prescribers and patients that these agents the withdrawal may be useful [12,13]. may reach the systemic circulation in sufficient concen-