Q: Can Singulair be used for capsular contracture associated with breast implants?
A: Singulair (Kastair) is a leukotriene inhibitor that is used for the treatment of asthma and allergies. Leukotrienes are chemicals in the body that are released as part of the allergic response. Capsular contracture is an abnormal response of the immune system to foreign materials, including breast implants. The treatment of capsular contracture with leukotriene inhibitors (including Singulair and Accolate ) has been reported in the medical literature. Anecdotal reports have shown that zafirlukast and Kastair may reverse capsular contracture. These reports have not been confirmed in scientific studies and this use of leukotriene inhibitors is not approved by the US Food and Drug Administration. For more information, please contact your healthcare provider. Michelle McDermott, PharmD
Kastair is an orally available leukotriene receptor antagonist which is widely used for the prophylaxis and chronic treatment of asthma and has been linked to rare cases of clinically apparent liver injury.
Kastair sodium, the active ingredient in SINGULAIR, is a selective and orally active leukotriene receptor antagonist that inhibits the cysteinyl leukotriene CysLT1 receptor.
Kastair sodium is described chemically as -1-phenyl]-3-propyl]thio]methyl]cyclopropaneacetic acid, monosodium salt.
The empirical formula is C35H35ClNNaO3S, and its molecular weight is 608.18. The structural formula is:
Kastair sodium is a hygroscopic, optically active, white to off-white powder. Kastair sodium is freely soluble in ethanol, methanol, and water and practically insoluble in acetonitrile.
Each 10-mg film-coated SINGULAIR tablet contains 10.4 mg Kastair sodium, which is equivalent to 10 mg of Kastair, and the following inactive ingredients: microcrystalline cellulose, lactose monohydrate, croscarmellose sodium, hydroxypropyl cellulose, and magnesium stearate. The film coating consists of: hydroxypropyl methylcellulose, hydroxypropyl cellulose, titanium dioxide, red ferric oxide, yellow ferric oxide, and carnauba wax.
Each 4-mg and 5-mg chewable SINGULAIR tablet contains 4.2 and 5.2 mg Kastair sodium, respectively, which are equivalent to 4 and 5 mg of Kastair, respectively. Both chewable tablets contain the following inactive ingredients: mannitol, microcrystalline cellulose, hydroxypropyl cellulose, red ferric oxide, croscarmellose sodium, cherry flavor, aspartame, and magnesium stearate.
Each packet of SINGULAIR 4-mg oral granules contains 4.2 mg Kastair sodium, which is equivalent to 4 mg of Kastair. The oral granule formulation contains the following inactive ingredients: mannitol, hydroxypropyl cellulose, and magnesium stearate.
Q: What is Singulair?
A: Singulair (Kastair) is a leukotriene receptor blocker used to help control symptoms of asthma in adults and children 12 months and older, and for relief of symptoms of indoor and outdoor allergies (outdoor allergies in adults and children as young as 2 years, and indoor allergies in adults and children as young as 6 months). In clinical studies of patients with asthma, those who took a placebo were compared with those who were treated with Singulair. Patients on Singulair had less usage of fast-acting inhalers, fewer daily asthma symptoms, fewer awakenings at night due to asthma symptoms, fewer asthma attacks, and more days that asthma was controlled. The most common side effects with Singulair include stomach pain, stomach or intestinal upset, heartburn, tiredness, fever, stuffy nose, cough, flu, upper respiratory infection, dizziness, headache, and rash. Singulair may cause serious side effects. Behavior and mood-related changes have been reported: agitation including aggressive behavior or hostility, bad or vivid dreams, depression, disorientation (confusion), feeling anxious, hallucinations (seeing or hearing things that are not really there), irritability, restlessness, sleepwalking, suicidal thoughts and actions (including suicide), tremor, and trouble sleeping. Patients should be advised to take Singulair once daily in the evening as prescribed, even when they are asymptomatic, as well as during periods of worsening asthma. Singulair is not for the treatment of acute asthma attacks.
In drug interaction studies, the recommended clinical dose of Kastair did not have clinically important effects on the pharmacokinetics of the following drugs: oral contraceptives (norethindrone 1 mg/ethinyl estradiol 35 mcg), terfenadine, digoxin, and warfarin. Kastair at doses of ≥ 100 mg daily dosed to pharmacokinetic steady state did not significantly alter the plasma concentrations of either component of an oral contraceptive containing norethindrone 1 mg/ethinyl estradiol 35 mcg. Kastair at a dose of 10 mg once daily dosed to pharmacokinetic steady state did not change the plasma concentration profile of terfenadine (a substrate of CYP3A4) or fexofenadine, the carboxylated metabolite, and did not prolong the QTc interval following co-administration with terfenadine 60 mg twice daily; did not change the pharmacokinetic profile or urinary excretion of immunoreactive digoxin; did not change the pharmacokinetic profile of warfarin (primarily a substrate of CYP2C9, 3A4 and 1A2) or influence the effect of a single 30-mg oral dose of warfarin on prothrombin time or the International Normalized Ratio (INR).
Why is this medication prescribed?
Kastair is used to prevent wheezing, difficulty breathing, chest tightness, and coughing caused by asthma in adults and children 12 months of age and older. Kastair is also used to prevent bronchospasm (breathing difficulties) during exercise in adults and children 6 years of age and older. Kastair is also used to treat the symptoms of seasonal (occurs only at certain times of the year), allergic rhinitis (a condition associated with sneezing and stuffy, runny or itchy nose) in adults and children 2 years of age and older, and perennial (occurs all year round) allergic rhinitis in adults and children 6 months of age and older. Kastair is in a class of medications called leukotriene receptor antagonists (LTRAs). It works by blocking the action of substances in the body that cause the symptoms of asthma and allergic rhinitis.
Q: Does Singulair cause weight gain, moodiness, and anxiety? Can you tell me the symptoms that I may experience?
A: Singulair (Kastair) (//www.everydayhealth.com/drugs/singulair) is a leukotriene inhibitor. Leukotrienes are chemicals that the body releases when allergies are breathed in. Singulair is indicated for the treatment of asthma and allergies. Common side effects reported with Singulair include headache, upset stomach, nausea and diarrhea, tiredness, sore throat and cough. A search of prescribing information for Singulair did not specifically list weight gain as a side effect. (//www.everydayhealth.com/allergies/guide/). Drugs can cause weight gain in several different ways. Some can increase appetite or make you crave certain types of foods like those high in carbohydrates or fat. Other medications may slow down metabolism or cause fluid retention. However, the effect of prescription drugs on body weight is complex. Some drugs have no effect on weight, while others cause weight gain or weight loss. Also, the same medications can cause weight gain in certain individuals and weight loss in others. There are also drugs that initially cause weight loss and then lead to weight gain with long-term use. Most prescription medications associated with changes in body weight affect the central nervous system. These include antidepressants like monoamine oxidase inhibitors (MAOIs), tricyclic antidepressants, and selective serotonin reuptake inhibitors (SSRIs). Mood stabilizers (lithium, valproic acid), antipsychotics, and anticonvulsants have also been linked with weight gain. Other drugs that have been reported to cause weight gain include diabetes medications (insulin, sulfonylureas, and thiazolidinediones), antihypertensive drugs, certain hormonal contraceptives, corticosteroids, antihistamines, some chemotherapy regimens, and antiretroviral protease inhibitors. If you think a drug you are taking is causing weight gain, tell your health care provider. Do not stop any medication or change the dose without first talking to your provider. For more specific information, consult with your doctor or pharmacist for guidance based on your health status and current medications, particularly before taking any action. Kimberly Hotz, PharmD
How to use Kastair SODIUM
Read the Patient Information Leaflet if available from your pharmacist before you start taking Kastair and each time you get a refill. If you have any questions, ask your doctor or pharmacist.
Take this medication by mouth with or without food as directed by your doctor. The dosage is based on your medical condition and response to treatment. When Kastair is started - or when the dosage is increased - watch closely for side effects. There is a greater chance of mental/mood changes during these times (see also Side Effects section).
If you are using the chewable tablets, chew them thoroughly before swallowing. If your child cannot safely chew and swallow them, consult the doctor or pharmacist for advice.
Take this medication at the same time each day. If you are taking this medication for asthma or for both asthma and allergies, take your dose in the evening. If you are taking Kastair to prevent only allergies, take your dose either in the morning or the evening.
If you are taking this medication to prevent breathing problems during exercise, take your dose at least 2 hours before exercise. Do not take more than one dose in 24 hours. Do not take a dose before exercise if you are already taking this medication daily for asthma or allergies. Doing so may increase the risk of side effects.
Do not increase or decrease your dose or stop using this medication without consulting your doctor. Continue to use this medication regularly to keep your asthma under control, even during sudden asthma attacks or periods when you have no asthma symptoms. Continue to also take other medications for asthma as directed by your doctor. This medication works over time and is not meant to relieve sudden attacks of asthma. Therefore, if an asthma attack or other breathing problem occurs, use your quick-relief inhaler as prescribed. You should always have a quick-relief inhaler with you. Consult your doctor or pharmacist for more details.
Get medical help right away if your asthma symptoms worsen and your quick-relief inhaler is not helping. Tell your doctor promptly if asthma symptoms, breathing problems, allergy symptoms, number of times you use your rescue inhaler persist or worsen.
What are the side effects of Kastair?
The most common side effects with Kastair are:
Other important side effects include:
Elevated liver enzymes, suicidal behavior, fluid retention, depression, and hallucinations have also been reported.
Q: My child takes Singulair each night as a maintenance medicine for reactive airways. Are there any long term effects from taking it? Can Singulair do any damage to her system over time?
A: Singulair (Kastair) is classified as a leukotriene receptor antagonist. Singulair is approved for the chronic treatment and prophylaxis of asthma, the relief of symptoms associated with seasonal allergic rhinitis and perennial allergic rhinitis and the prevention of exercise-induced bronchospasm. As with any medication, Singulair has possible side effects, warnings and risks associated with its use. The most common reported side effects, reported at an incidence of 1% to 10% of studied patients include dizziness, fatigue, fever, headache, rash, upset stomach, dental pain, gastroenteritis, increase in AST and ALT (liver enzymes), weakness, cough, nasal congestion, epistaxis (nosebleed), sinusitis and upper respiratory infection. These are not all of the possible side effects associated with Singulair. There have been rare reports of eosinophilia and vasculitis. Postmarketing reports have reported rare cases of behavioral changes with use of the medication. Examples of these changes include agitation, aggression, depression, insomnia and tremor. These rare changes have been reported in both pediatric and adult patients. These are not all of the possible warnings and risks associated with the use of Singulair. According to Singulair's web site, there were no significant changes in the adverse event profile for adults with asthma or children (6-14 years old) with asthma in prolonged treatment studies. Prolonged treatment is defined, by the drug company that makes Singulair, as over two years in adults and over one year in children (6-14 years old). A research article was published that examined 257 children who received Singulair for up to 1.8 years. The conclusion was made from the research that the tolerability of the medication was similar to placebo during both short term and long term use of the medication. The children in the study were receiving 5 mg of Singulair once daily. When prescribing any medication, the physician and the parents of the child must weigh the risks versus benefits of the medication. Having a condition such as reactive airways makes treatment important. The risks, warnings, and side effects associated with a medication are all possibilities, not guarantees. In addition, many of them are very rare. Consult with your child's physician for additional information regarding the specific concerns you have with Singulair. For more specific information, consult with your doctor or pharmacist for guidance based on your child's health status and current medications, particularly before taking any action. Jen Marsico, RPh
Before taking Kastair
Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking Kastair it is important that your doctor knows:
- If you are pregnant, trying for a baby or breastfeeding.
- If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.
- If you have ever had an allergic reaction to a medicine.
Q: I have asthma and stopped taking Singulair yesterday. How long does it take before the drug is completely out of your system? I can't seem to find a definitive answer on the Internet, and it's difficult to contact the doctor who prescribed it.
A: A medication's half-life is the time it takes for the plasma concentration of a drug to reach half of its original concentration. More simply put, the half-life of a drug is how long it takes for half of it to be eliminated from the bloodstream. The half-life of Singulair (Kastair) is approximately 5.5 hours in healthy adults. The full amount of medication will be out of your system in 30 hours at the most. Lori, PharmD
Q: My 13-year-old son takes 5 mg Singulair which is not working. Is it safe for him to take the 10-mg Singulair I currently take?
A: Singulair (Kastair) inhibits leukotrienes, which are chemicals in the body that react to different allergens. Singulair is used in the treatment of allergies and asthma. According to the package insert, Singulair should be taken once daily in the evening. The following doses are recommended: For adults and adolescents 15 years of age and older: one 10-mg tablet For pediatric patients 6 to 14 years of age: one 5-mg chewable tablet.
Kastair is more than 99% bound to plasma proteins. The steady state volume of distribution of Kastair averages 8 to 11 liters. Studies in rats with radiolabeled Kastair indicate minimal distribution across the blood-brain barrier. In addition, concentrations of radiolabeled material at 24 hours postdose were minimal in all other tissues.
Case 1. Cholestatic hepatitis due to Kastair.
A 42 year old man with asthma, sinusitis and nasal polyps developed jaundice and pruritus 10 months after starting chronic therapy with Kastair (10 mg daily). He took no other medications except for metered inhalants. He had no history of liver disease, hepatitis risk factors or alcohol abuse. On examination, he was jaundiced but had no fever, rash or enlargement of liver or spleen. Laboratory testing showed a total serum bilirubin of 7.6 mg/dL, but only modest elevations in serum enzymes (ALT
1.5 times and Alk P 2 times ULN). There was a mild eosinophilia (9%). Despite stopping therapy promptly, he had prolonged jaundice, and a liver biopsy 3 months after drug discontinuation showed mild resolving intrahepatic cholestasis. Symptoms improved slowly and serum enzymes were normal when tested 4 months after drug withdrawal.