Asthma inhalers: types and use
Bronchial asthma is a severe disease which characterizes by chronic inflammation of respiratory tract and bronchial hypersensitivity. Contact with an allergen, emotional stress, cold air — any of these can cause another asthma attack, threatening the life of a patient.
In last decades, medical specialists were able to achieve significant progress in healing asthma. Contemporary medicines have great efficiency and can control the disease, protecting patients from serious exacerbations.
All the medicines, used to treat asthma can be divided into two large groups:
Broncholytics - they prevent bronchospasms, widening the gap for the airflow
Anti-inflammatory drugs that reduce edema and also ease the breath of patient
Bronchial asthma inhalers
In case of bronchial asthma, inhalers are the perfect way to deliver the medicine directly into the required zone. Injections or oral use of the medicine makes it travel through many blood vessels, liver and spread around the whole body.
Bronchial asthma attack is not the condition that lets you wait for a dozen minutes before the medicine takes effect. When the solution is spread right into the needed zone, it starts working immediately. Additionally, inhaler is very simple to use. Injection requires implementation of the rules of antisepsis and demands certain skill of the doer. Children are often afraid of injections, while they take inhalers positively.
Those reasons make inhaler true panacea for bronchial asthma, without any anticipated replacement in foreseeable future.
Inhaler is a special device, procuring the delivery of medicine into the respiratory tract of the patient. The first represented inhaler, shown in 1874, was simple and bulky, but now there are several kinds, each with its pluses and minuses.
Dry powder inhalers:The devices procure the delivery of a set dose of dry powder into the organism. Their pros are simple use and high efficiency. However, they are slightly more expensive than the other types of inhalers.
Spacers: Those are cameras, made of plastic or metal, which are attached to the inhaler. They play a role of a valve: the medication gets into the lung only when the patient breathes in. The valve shuts during the exhalation, and the medication is not spent in vain.
Spacer significantly simplifies the inhalation and procures the deep pervasion of the medicine in lungs. We should mention the use of spacers in treatment of children: they are not always able to breathe correctly during the inhalation, and the device makes the medicine get into the organism independently on how the patient breathes.
The disadvantage of spacers is their large size: it’s not always convenient to carry the inhaler and the spacer (the device is often larger than the pocket inhaler).
Liquid dosage inhaler: The device provides the ejection of a certain amount of the medication in an aerosol form. Its advantage is its price and simple and reliable construction. Its minus is that it requires the simultaneous breath in during the ejection of the medication. It takes more time to learn, though an adult easily does that. Also, the aerosol is heavier than powder and inevitably deposits in mouth, getting swallowed. However, the producers take this fact into account when setting the dose.
It’s a name for devices for inhalations that provide spraying of the medications into very tiny fractions. Thanks to that method, the light particle reaches the most distant sites of the respiratory tract and the better effect is achieved. By the principle of action nebulizers are divided into compressor and ultrasonic (special membrane vibrates and splits the substance into fractions).
Nebulizers are usually bulky (compared to pocket inhalers), which doesn’t allow carrying them and using in case of emergency, but they are perfect for use at home.
The amount of portative nebulizers grows in recent years. They can work from batteries, but they are not widely spread yet and are relatively expensive.
After a sequence of researches, medical specialists have discovered that many patients make mistakes that lower the efficiency of treatment during inhalation. The creation of inhalers, activated by the breath in of patient, was a brilliant solution for such problem. The device senses when the airflow rushes in lungs and ejects the needed dose by itself.
The most popular inhalers
Today one can find a great diversity of medications for asthma in each drugstore. Patient should know that the brand name of the asthma inhalers (Turbuhaler, Pulvinal, Diskus, Easyhaler, Diskhaler and many others) are not always the name of the medication. One active substance can sell under different brand names.
As it’s been said before, all the asthma medications divide into two large subgroups: broncholytics and anti-inflammatory drugs.
Sympathomimetic drugs - medications that stimulate bronchial receptors and widen the air gap. Now the most popular type of those is short-action selective adrenomimetic drugs, because they soothe the attack of the disease quickly and excrete fast. Common names are salbutamol, pirbuterol, terbutalin, levalbuterol etc.
M-cholinoreceptor blockers - act through the bronchial relaxation. From the whole group, only ipratropium (atrovent) is useful for the patients with bronchial asthma. This substance is poorly absorbed in gastrointestinal tract, so it’s used only through inhalation.
Methylxanthines possess a complicated mechanism of action, based on the inhibition of particular ferments in the body. As a result of their action, smooth bronchial muscles relax, and the broncholytic effect is achieved. Theophylline and aminophylline belong to this drug group.
Glucocorticoids are drugs with a powerful anti-inflammatory effect, which is achieved by several independent mechanisms (adrenaline effect is empowered; the edema of bronchial mucosa is removed). Those medications are often associated with a large number of adverse effects in case of systemic use; so many inhalational medications were created. They get directly into lungs and don’t possess such variety of side effects.
Anti-inflammatory drugs in asthma treatment
Inhalational glucocorticoids are the great solution for prevention of medium severity asthma attacks. Medicines that belong to that group are beclometason, budesonide, fluticasone, flunisolide.
Mast cell stabilizers - medications, preventing the release of biologically active substances, causing inflammatory reaction and edema of bronchial mucosa, from leukocytes.
(The medications are not spread widely, but pediatricians use them to prevent exercise-induced asthma and allergic conjunctivitis in children. They are not produced as inhalers, but are actively used as simple aerosols, designed for irrigation of nasal mucosa. Representatives of the group: cromolin and nedocromil.)
Leukotriene inhibitors (zafirlukast, montelukast, zileuton) - prevent the formation of those active substances and the development of mucosal edema. Not used as inhalers, but are often applied together with them for treatment of aspirin-induced asthma.
Anti-immunoglobulin E (omalizumab) - antibodies, inhibiting the binding of immunoglobulin E to mast cells. The medication is used when asthma is not responding to other methods and drug combinations. It’s characterized by high cost, but also guarantees a prolonged effect.
Despite the variety of solutions for bronchial asthma, the standard treatment for most patients consists in use of short-action selective beta-adrenomimetic (“when needed”) together with an inhalational glucocorticoid. Pediatric practice also includes the active use of mast cell membranes stabilizers.
It’s impossible to describe all the inhalers, used for treatment of bronchial asthma, in one article, and it’s not necessary. All of them contain the above substances in various combinations and dosages. Attending doctor prescribes a certain medication after the medical examination of the patient, depending on the examination results.