Why Take Montelukast At Night?

What happens if you take montelukast in the morning?

Abstract – Montelukast is recommended to be taken in the evening. The effectiveness of this drug to prevent exercise-induced bronchoconstriction (EIB) in children was already evaluated. However, there is no information to determine if this effectiveness could vary depending on dosage time. Children (n = 24) with a documented history of EIB performed an exercise challenge test before starting montelukast treatment. Twelve children were randomly allocated to receive the drug in the morning for 2 weeks, and another 12 to receive it in the evening. After this treatment period and after a week of washout, the children were crossed over. An exercise test was repeated after the first and second periods of treatment. Values obtained after morning or evening dosage were compared with pretreatment values for the whole group of children. There was a significant effect of montelukast for protecting against EIB, measured both as percent of maximum fall in forced expired volume in 1 sec (FEV1) (18.9 +/- 9.7, morning, 18.7 +/- 11.3, evening, vs.27.5 +/- 9.8, pretreatment; P < 0.05) or as area under the curve (156.4 +/- 102.0, morning, 145.4 +/- 130.6, evening, vs.294.3 +/- 156.5, pretreatment; P < 0.005). There were no statistical differences between taking the drug in the morning or evening. In conclusion, montelukast, taken for 2 weeks, is equally effective in exercise-induced bronchoconstriction when dosing either in the morning or in the evening. (c) 2006 Wiley-Liss, Inc.

Does montelukast make you sleepy?

Montelukast Montelukast works by preventing narrowing of your airways brought on by inflammation. Taking Montelukast helps in breathing easily and preventing asthma attacks. It is essential that you take Montelukast at night to avoid asthma attacks. Yes, if you are taking Montelukast, you can drink alcohol.

There are no food or drink restrictions associated with Montelukast. However, it is best to avoid cold drinks when you have asthma or allergy issues. No, Montelukast is not a decongestant. It belongs to the group of drugs called leukotriene receptor antagonists. This medicine works by blocking natural substances called leukotrienes.

Montelukast is an FDA-approved medicine for allergies and asthma. It is prescribed in adults and children to prevent asthma attacks and exercise-induced asthma. Montelukast is generally prescribed for an extended period. This medicine is meant to be taken as a long-term treatment.

• Take the dose of Montelukast as prescribed by your physician.
• You can consult our expert to get a medical opinion before changing your dosage of Montelukast.
• Montelukast is a leukotriene receptor antagonist.
• It works by blocking the action of leukotrienes, which are natural substances present in bodies.

These substances are released on coming in contact with an allergy trigger or an allergen. Yes, Montelukast helps prevent asthma attacks. This medicine prevents the narrowing of airways and helps ease breathing. Do not stop taking this medicine even when you feel better.

• You can consult our expert to get a medical opinion before changing your dosage of Montelukast.
• No, Montelukast is not a steroid.
• It belongs to the group of drugs called leukotriene receptor antagonists.
• This medicine prevents the action of natural substances known as leukotrienes.
• Montelukast can cause psychiatric-type effects that include aggression, agitation, anxiety, depression, hallucinations, and abnormal dreams.

This medicine can also cause drowsiness and dizziness and affect your ability to drive or operate heavy machinery. No, Montelukast is not an antihistamine. It belongs to the group of drugs called leukotriene receptor antagonists. Montelukast blocks the action of natural substances known as leukotrienes in your body.

Why do you have to take montelukast on an empty stomach?

How to take chewable tablets – It’s important to take chewable tablets at least 1 hour before food, or 2 hours after food. This is so the medicine is absorbed into your body properly. Chewable tablets can be chewed or sucked. You or your child can have a drink of water or squash afterwards.

Does montelukast help immediately?

How does montelukast work? Montelukast is from a group of medicines called leukotriene receptor antagonists (LTRAs). LTRAs work by stopping the chemicals in your body that narrow your airways. These chemicals are called leukotrienes. Montelukast helps stop your airways from narrowing (caused by inflammation).

This makes breathing easier and prevents asthma attacks. Leukotrienes are also released in your body when you have an allergic reaction to something like dust or pollen and when you exercise. Montelukast helps to reduce the level of leukotrienes and stops you getting symptoms. When will I feel better? Montelukast starts to work immediately and takes about a day to start to help asthma symptoms.

If montelukast has had no effect after you’ve been taking it for 4 to 8 weeks, see your doctor to talk about other treatment options. If you’re taking montelukast to prevent exercise-induced asthma, take it 2 hours before you exercise. This will mean that the level of medicine in your body is highest when you start exercising.

1. Are there any long-term side effects? There’s no evidence to suggest that taking montelukast will cause any problems if you take it for a long time.
2. Are there any other medicines for asthma? Montelukast is one medicine used to prevent asthma symptoms.
3. Most people with asthma will be given an inhaler, such as beclometasone or fluticasone,

Montelukast may be given as an extra medicine if your doctor thinks you need it. Other medicines which may help prevent asthma attacks are inhalers like salmeterol or sodium cromoglicate, or medicines like theophylline. Medicines used to relieve asthma symptoms quickly when they come on include salbutamol or terbutaline inhalers.

Will it affect my contraception? Montelukast does not affect any type of contraception including the combined pill and emergency contraception, However, if montelukast makes you vomit or have severe diarrhoea for more than 24 hours, your contraceptive pills may not protect you from pregnancy. Look on the pill packet to find out what to do.

Read more about what to do if you’re on the pill and you’re being sick or have diarrhoea, Can I drive or ride a bike? Montelukast does not usually cause any problems with driving or riding a bike. However, do not drive a car or ride a bike if montelukast makes you see things which are not there (hallucinate), if you get shaking or tremors in any part of your body or you’re unable to concentrate or make decisions.

It’s your responsibility to decide if it’s safe to drive. If you’re in any doubt, do not drive. Talk to your doctor or pharmacist if you’re unsure whether it’s safe for you to drive while taking montelukast. GOV.UK has more information on the law on drugs and driving, Can I drink alcohol while taking montelukast? Yes, you can drink alcohol while taking montelukast.

Is there any food or drink I need to avoid? You do not need to avoid any food or drink while taking montelukast. Page last reviewed: 14 March 2023 Next review due: 14 March 2026

What should I avoid while taking montelukast?

Cautions with other medicines – There are some medicines that may affect how montelukast works. Tell your doctor or pharmacist if you’re taking any of these medicines:

epilepsy medicines such as phenobarbital or phenytoin rifampicin, for tuberculosis and some other infectionsgemfibrozil, for high cholesterol

It’s usually safe to take everyday painkillers with montelukast. However, do not take non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin or ibuprofen if they’ve ever made your asthma symptoms worse.

Does montelukast get rid of mucus?

Abstract – Sputum eosinophilia is a sensitive predictor of benefit from corticosteroid treatment. Montelukast is a cysteinyl leukotriene antagonist, which also reduces sputum and blood eosinophils. The present study examined the possibility that montelukast has an added eosinophil-lowering effect in subjects with asthma who are corticosteroid responsive but relatively corticosteroid resistant. A total of 14 clinically stable adults with asthma requiring minimum treatment with a high-dose inhaled steroid or prednisone, with baseline sputum eosinophilia (> or =5%), were randomised to receive 4 weeks of 10 mg montelukast or placebo daily in a double-blind crossover trial. The primary outcome was the effect of treatment on the percentage of sputum eosinophils. Secondary outcomes were changes in the blood eosinophil count, symptoms, forced expiratory volume in one second, peak expiratory flow and the need for salbutamol. The median (interquartile range, i.e.75th-25th centile) for sputum eosinophils at baseline was 15.7% (22). The effect of adding montelukast was not significantly different from that of placebo, sputum eosinophils being 9.3% (18.9) after montelukast and 11.3% (22.8) after placebo. No difference was detected on secondary outcomes. No crossover interactions were observed. In conclusion, the addition of montelukast to existing high-dose corticosteroid therapy in subjects with asthma with elevated sputum eosinophils does not provide additional attenuation of airway eosinophilia.

What does montelukast do to your brain?

In particular, montelukast appears to reduce blood-brain barrier (BBB) permeability, which may lead to secondary protection from some injuries and age-related diseases.

Is montelukast a strong antihistamine?

What is montelukast’s classification? Is it a steroid or antihistamine? – Montelukast is classified as a leukotriene receptor antagonist. It’s not a steroid or an antihistamine, But it’s often prescribed in combination with a steroid or antihistamine to treat asthma and allergic rhinitis,

Does montelukast cause weight gain?

Does montelukast (Singulair) cause weight gain? Weight gain isn’t a common side effect of montelukast (Singulair). Contact your provider about your concerns if you notice unexpected weight gain.

How quickly does montelukast work?

How long does it take to see results? – Montelukast starts reducing leukotriene levels immediately. However, it may take about a week to effectively combat the symptoms of chronic asthma and allergies. Taking montelukast two hours before exercising typically provides noticeable results for patients with bronchoconstriction during exercise.

How long can montelukast be taken?

5. Tips –

May be taken with or without food. Available as tablets, chewable tablets, and oral granules. The granules can be administered directly into the mouth or dissolved in a teaspoonful of breast milk or formula, or soft food such as applesauce, carrots, rice, or ice cream. Once the packet is opened, the contents should be taken within 15 minutes. Discard any unused portion. Take once daily in the evening when used as a preventative treatment for asthma. Take montelukast daily as prescribed, even if you have no symptoms of asthma. Do not take another dose of montelukast within 24 hours of a previous dose. Do not increase or decrease the dose of montelukast without your doctor’s permission and continue to take all other asthma medications as prescribed. Take montelukast two hours before exercise when using to prevent exercise-induced bronchospasm (EIB). If you are already taking montelukast on a daily basis, you do not need to take an additional dose to prevent EIB. Take exactly as prescribed when given for asthma, even if you are asymptomatic. Continue taking as prescribed even during an acute asthma attack. If you miss a dose, take it as soon as possible. But if it is almost time for your next dose, just skip that dose. Do not double up on doses. Chewable tablets are typically taken once daily in the evening (although studies have not been conducted to evaluate if there is any difference in effectiveness with morning dosing). Chew the tablets thoroughly before swallowing. If you are having an acute asthma attack, take your short-acting bronchodilator medicine (for example, albuterol) as prescribed. Talk to your doctor if you regularly need to take more of your acute asthma treatment. Notify your doctor if you experience any neuropsychiatric effects (such as aggression, anxiety, depression, or hallucinations) while taking montelukast. Also, tell your doctor if you develop any symptoms of an allergic reaction including a rash or breathing problems; or side effects such as an abnormal heartbeat, unusual bruising, yellowing of the skin or eye, trouble sleeping, or a tingling or twitching in your fingers and toes. Avoid driving or operating machinery if montelukast makes you drowsy or dizzy. If you know you are sensitive to aspirin or other NSAIDs, continue to avoid these while taking montelukast. If you have phenylketonuria, be aware that the 4 and 5mg chewable tablets contain phenylalanine. Tell your doctor if you are breastfeeding, pregnant, or intending to become pregnant because they will need to discuss the risks versus benefits of using montelukast while pregnant or breastfeeding.

What happens if you suddenly stop taking montelukast?

And while stopping Singulair may not cause withdrawal symptoms or make your asthma worse, it’s best to talk with a healthcare provider first. Very rarely, Singulair can cause more serious side effects, like allergic reactions, joint and muscle pain, or heart palpitations.

What is the most common side effect of montelukast?

Common side effects of montelukast include upper respiratory infection, fever, headache, sore throat, cough, stomach pain, diarrhea, earache or ear infection, flu, runny nose, and sinus infection.

Is it worth taking montelukast?

Frequently Asked Questions –

• Is Singulair an antihistamine? No. Singular blocks leukotrienes, not histamines. Leukotrienes cause allergy symptoms like coughing, inflammation in the airways, and trouble breathing.
• Is Singulair usually recommended for seasonal allergies? No. The FDA recommends trying other medications before turning to Singulair (montelukast) for allergic rhinitis or mild asthma symptoms. It can increase the risk of agitation, depression, sleeping problems, and suicidal thoughts and actions. In 2020, Singulair added a black box warning label to call out these risks.
• Can montelukast be used to treat COVID? Maybe. Some evidence shows that montelukast can help prevent people hospitalized with COVID-19 from developing more serious symptoms. But more research needs to be done.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

1. Kaur G, Dhingra R, Singh M, Kaur M. Montelukast: a better alternative than antihistaminics in allergic rhinitis, International Journal of Otorhinolaryngology and Head and Neck Surgery.2017(3)2. doi:10.18203/issn.2454-5929.ijohns20171185
2. U.S. Food and Drug Administration. FDA requires stronger warning about risk of neuropsychiatric events associated with asthma and allergy medication Singulair and generic montelukast,
3. U.S. Food and Drug Administration. FDA requires boxed warning about serious mental health side effects for asthma and allergy drug montulekast (Singulair); advises restricting use for allergic rhinitis,
4. American College of Allergy, Asthma and Immunology. Allergic rhinitis,
5. Alkeraye S, AlRuhaimi DK. The addition of montelukast for the treatment of chronic idiopathic urticaria, Cureus,2021 Jul 3;13(7):e16137. doi:10.7759/cureus.16137
6. Chin WK, Lee SWH. A systematic review on the off-label use of montelukast in atopic dermatitis treatment, Int J Clin Pharm,2018 Oct;40(5):963-976. doi:10.1007/s11096-018-0655-3
7. Harvard Health Publishing. Harvard Medical School. Allergic rhinitis: your nose knows.
8. Cingi CC, Muluk NB, Hanci D, Sahim E. Impacts of allergic rhinitis in social communication, quality of life and behaviours of the patients, J Allergy Disord Ther.2015;2(1):002. doi:10.24966/ADT-749X/100002
9. Cuzzo B, Lappin SL. Physiology, Leukotrienes,, In: StatPearls, Treasure Island (FL): StatPearls Publishing; 2023 Jan-.
10. Drugs.com. Singulair: 7 things you should know,
11. Drugs.com. Singulair,
12. Aypak C, Türedi Ö, Solmaz N, Yıkılkan H, Görpelioğlu S. A rare adverse effect of montelukast treatment: ecchymosis, Respir Care,2013;58(9):e104-6. doi:10.4187/respcare.02298
13. Tamada T, Ichinose M. Leukotriene receptor antagonists and antiallergy drugs, Handb Exp Pharmacol,2017;237:153-169. doi:10.1007/164_2016_72
14. Mohamed Hussein AAR, Ibrahim MEAA, Makhlouf HA, et. al. Value of montelukast as a potential treatment of post-COVID-19 persistent cough: a non-randomized controlled pilot study, Egypt J Bronchol.2022;16(1):52. doi:10.1186/s43168-022-00154-6

By Daniel More, MD Daniel More, MD, is a board-certified allergist and clinical immunologist. He is an assistant clinical professor at the University of California, San Francisco School of Medicine and currently practices at Central Coast Allergy and Asthma in Salinas, California. Thanks for your feedback!

Do I really need to take montelukast?

Montelukast Montelukast is a type of medicine known as a leukotriene receptor antagonist. Most people with asthma do not need montelukast, but it can be a useful add-on treatment to take alongside your usual, Montelukast is not a steroid – it works in a different way to reduce inflammation.

Can you take vitamins with montelukast?

Interactions between your drugs No interactions were found between montelukast and Vitamin D3.

Does montelukast affect the heart?

Introduction – Inflammation is a physiological reaction that, when dysregulated, can become a pathological process associated with several diseases characterized by the release of mediators, including metabolites of arachidonic acid. Cysteinyl leukotrienes (cysteinyl-LTs), namely, LTC 4, LTD 4, and LTE 4, are derived from arachidonic acid and are potent proinflammatory lipid mediators well-known to play an important role in asthma ( Nicosia et al., 2001 ), and that have also been implicated in other inflammatory conditions, such as allergic rhinitis (AR), atopic dermatitis, and urticaria ( Capra et al., 2007 ).

Unlike many other inflammatory mediators, cysteinyl-LTs are not decreased by steroid use in asthmatics ( Gyllfors et al., 2006 ) Additionally, cysteinyl-LT involvement has been hypothesized in several cardiovascular diseases (CVDs), such as acute myocardial infarction (MI), ischemic stroke (IS), atherosclerosis, aortic aneurysms, and intimal hyperplasia ( Folco et al., 2000 ; Back, 2009 ; Poeckel and Funk, 2010 ; Capra et al., 2013 ).

Increased intracoronary production of cysteinyl-LTs was detected in patients undergoing coronary angioplasty ( Brezinski et al., 1992 ) and by systemic urinary LTE 4 excretion in acute MI and ischemic heart disease patients ( Carry et al., 1992 ; Allen et al., 1993 ; De Caterina et al., 2010 ).

Several proteins in the 5-lipoxygenase pathway, including both CysLT receptors, were found in the arterial wall of patients at different stages of atherosclerosis ( Allen et al., 1998 ; Lötzer et al., 2003 ; Spanbroek et al., 2003 ; Di Gennaro et al., 2010 ). Finally, besides the increase in cysteinyl-LTs concentration in CVD, a number of genetic studies also support a link between cysteinyl-LTs, their receptors, and CVD ( Helgadottir et al., 2004 ; Iovannisci et al., 2007 ; Bevan et al., 2009 ; Freiberg et al., 2010 ).

In the 1990s, after the discovery of an important role for cysteinyl-LT in asthma, 5-lipoxygenase pathway inhibitors and CysLT 1 receptor antagonists (LTRAs) were developed and are now widely used to treat asthma and other allergic conditions ( Capra et al., 2006 ).

• In CVD, and particularly in atherosclerosis, there is a crucial inflammatory component ( Ross, 1999 ; Back and Hansson, 2015 ).
• Given an important role for cysteinyl-LTs in modulating vascular tone and inflammation ( Sala et al., 2000 ; Bäck, 2007 ; Back et al., 2014 ), LTRAs have been proposed for potential therapeutic use in such diseases ( Funk, 2005 ; Capra et al., 2013 ).

The potent and selective CysLT 1 receptor antagonist montelukast was first approved by the Food and Drug Administration to be used in different stages of asthma both in adults and children and later on also for the treatment of seasonal and perennial AR ( Capra et al., 2006 ).

In addition, in preclinical animal models, montelukast significantly reduces the formation of atherosclerotic plaques and intimal hyperplasia and reduces reactive oxygen species and apoptosis, demonstrating beneficial effects on endothelial cell function and myocardial remodeling ( Capra et al., 2013 ; Hoxha et al., 2017 ).

Furthermore, montelukast inhibited oxidized low-density lipoprotein-induced monocyte adhesion to endothelial cells, suggesting a preventative role in the early stages of atherosclerosis ( Di et al., 2017 ). Montelukast is also protective against aorta dilatation, and it reduces aortic rupture and aneurism development in three independent animal models of abdominal aortic aneurysm ( Di Gennaro et al., 2018 ).

Therefore, a large body of preclinical research has shown a role of LTRAs in general, and of montelukast in particular, in controlling and reducing CV risk ( Funk, 2005 ; Hoxha et al., 2017 ). Indeed, asthmatic patients receiving montelukast have lower levels of CV disease-associated inflammatory biomarkers and lipid levels ( Allayee et al., 2007 ).

A recent nationwide cohort study on incident or recurrent ischemic events provided a first indication for a role of montelukast for secondary prevention of CVD ( Ingelsson et al., 2012 ). In order to explore a potential CVD preventive role for montelukast, we performed a 3-year observational retrospective study including eight hundred asthmatic patients exposed or nonexposed to montelukast and assessed the efficacy of montelukast in prevention of a major CV event such as heart attack or IS.

Can you take montelukast and paracetamol together?

Interactions between your drugs No interactions were found between montelukast and Pharmacist Paracetamol. However, this does not necessarily mean no interactions exist. Always consult your healthcare provider.

Does montelukast stop coughing?

Research summary – Persistent cough is a common symptom, accounting for about 20% of referrals to outpatient chest clinics. Most coughs are caused by self-limiting viral infections such as the common cold. However, 1 in 4 people with a viral infection develop a persistent cough, which can go on for several weeks.Whooping cough is a common cause of persistent cough in young people and adults.

1. Although the whooping cough vaccine gives lifelong protection against severe infection, it does not appear to give such long-term protection against milder infections, which can make someone cough for many weeks.
2. There are currently no proven efficacious treatments for persistent cough following either a viral infection or infection with whooping cough.Montelukast is a medication which is already licensed for the treatment of asthma.

It works by blocking the action of chemicals called leukotrienes, which make the airways of people with asthma inflamed and sensitive. There is strong evidence to suggest that leukotrienes are also involved in causing persistent cough following viral or whooping cough infection.

Montelukast may therefore also help settle persistent coughs in these settings.Over 18 months, we will recruit patients aged 16-49 years with a cough lasting 2-8 weeks from general practices in England. An oral fluid sample will be taken from each participant to be tested for whooping cough. Participants will be randomly allocated to receive a 28-day course of montelukast or placebo tablets and asked to complete a daily cough diary for two weeks.

They will be assessed after two weeks by their GP (face-to-face) and after four weeks by another member of practice clinical staff (telephone). Some participants will be given a 24-hour cough monitor to wear on study entry and at two-week follow-up.This study will be funded by the National Institute for Health Research??s School of Primary Care.

Why do I feel like I have mucus stuck in my throat all the time?

There are many possible causes of frequent or constant throat clearing. These range from allergies and acid reflux to medication side effects and eating habits. A person may clear their throat often because it feels as though something is tickling or stuck in the throat.

1. These sensations can occur even when nothing is there.
2. Throat clearing itself is not a medical condition, but it can be a symptom of one.
3. In this article, we explore some possible causes of frequent throat clearing.
4. We also explain when to see a doctor and list the general treatment options.
5. The sinuses, throat, and nose all produce mucus that a person usually swallows unconsciously.

When mucus starts to build up or trickle down the back of the throat, this is known as postnasal drip, Causes of postnasal drip include infections, allergies, and acid reflux, As well as feeling the need to clear the throat frequently, a person with postnasal drip may also experience :

a sore throat hoarseness frequent swallowing

What is the best medicine to remove thick mucus?

Expectorants – Expectorants thin mucus and allow more effective coughing to clear airways. Guaifenesin is a common expectorant that is particularly effective at relieving congestion in the chest. People first began using natural forms of guaifenesin in the 1500s,

fast-acting tabletsextended-release tabletsliquid medications

Individuals taking medications with guaifenesin should stay hydrated and follow all doctor recommendations.

Can you take montelukast in the morning for allergies?

Overdose – If someone has overdosed and has serious symptoms such as passing out or, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.

Symptoms of may include: thirst, drowsiness, inability to keep still,, or severe, Notes Do not share this with others. Lab and/or medical tests (such as function) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details. Missed Dose If you miss a dose, skip the missed dose.

Take your next dose at the regular time. Do not double the dose to catch up. Do not take more than 1 dose in 24 hours. Storage Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all away from children and pets. Do not flush medications down the toilet or pour them into a drain unless instructed to do so.

How quickly does montelukast work?

How long does it take to see results? – Montelukast starts reducing leukotriene levels immediately. However, it may take about a week to effectively combat the symptoms of chronic asthma and allergies. Taking montelukast two hours before exercising typically provides noticeable results for patients with bronchoconstriction during exercise.

What happens if I accidentally take 2 montelukast?

What happens if you take too much montelukast? – If you take too much montelukast, you may be at a higher risk of developing unwanted side effects. In some studies, daily dosing up to 200 mg was safe in adult patients. Another study analyzed montelukast exposures involving children five years old or younger and concluded that doses up to 536 mg were unlikely to have serious side effects.

How long does montelukast stay in your system?

Medically reviewed by Drugs.com, Last updated on Oct 24, 2022. Singulair (montelukast) will be in your system for approximately 30.3 hours. The mean plasma half-life of montelukast ranges from 2.7 to 5.5 hours in healthy young adults. This is the time it takes for your body to reduce the plasma levels by half.

• It takes approximately 5.5 x half-life for a drug to be out of your system therefore Singulair will be in your system for approximately 5.5 x 5.5 hours = 30.3 hours Other factors also need to be taken into account and include: 1.
• How much and how often you have taken the drug.2.
• Your metabolic rate – a slower metabolism will increase the time a drug remains in your system.3.

Your age and health – older age and poor health will generally increase the time the drug stays in your system.4. Body mass – generally the bigger you are the longer a drug will remain in your system. Singulair (montelukast) belongs to a group of medications known as leukotriene receptor antagonists.