Asthma Medication

Respiratory Drugs

• Drugs can affect dilation or constriction of the airway through the autonomic nervous system.

Autonomic Nervous System

• Sympathetic stimulation leads to bronchodilation, while parasympathetic stimulation leads to bronchoconstriction.
• Sympathetic stimulation: Adrenergic drugs are used
• Parasympathetic inhibiton: Anticholinergics are used
• Cholinergic drugs act on the parasympathetic nervous system.
• Adrenergic drugs affect the sympathetic nervous system.

Drugs for Respiratory Diseases

Bronchodilators

• Beta-2 agonists, anticholinergics, and methylxanthines are classes of bronchodilators.

Beta-2 Agonists

• Beta-2 agonists activate beta-2 adrenergic receptors in smooth muscle of bronchi, gut, uterus and blood vessels.
• Beta-2 agonists stimulate the sympathetic nervous system, resulting in fight or flight response
• Beta-2 agonists stimulate airway dilation and treat asthma and COPD

Short Acting Beta-2 Agonists (SABA)

• SABAs are effective for relieving acute bronchospasm as first-line medications for acute asthma attacks.
• SABAs work by bronchodilation with an onset of action is under 5 minutes and the therapeutic effect lasts 3 to 6 hours.
• Examples of SABAs: salbutamol/albuterol (Ventolin) and terbutaline sulfate (Bricanyl).
• Use hydrofluoroalkane (HFA) inhalers instead of chlorofluorocarbon (CFC) inhalers

Long Acting Beta-2 Agonists (LABA)

• LABAs are used in combination with corticosteroids to prevent inflammation of the bronchi in chronic asthma patients.
• LABAs have a 12 hour duration of action when preventing inflammation
• Examples of LABAs: salmeterol (Serevent), formoterol (Symbicort), indacaterol (Onbrez), and olodaterol (Striverdi)
• Use hydrofluoroalkane (HFA) inhalers instead of chlorofluorocarbon (CFC) inhalers
• LABAs should never be used as a monotherapy

Beta-2 Agonists Side Effects

• Side effects include, tachycardia, palpitations, arrhythmias, anxiety, and muscle tremors.

Anticholinergics

• Anticholinergics such as antimuscarinics/antispasmodic/cholinergic blockers can be used
• Anticholinergics block acetylcholine binding to cholinergic/muscarinic receptors in smooth muscle
• Anticholinergics reduce smooth muscle tone in the respiratory tract

Anticholinergic Indications

• Can dilate the airway and treat bronchospasm while only mimicking fight or flight

Anticholinergic Side Effects

• Drowsiness, blurred vision, dry mouth, tachycardia, palpitation, constipation, and urinary retention are negative side effects
• Side effects of inhalation are lower than oral or IV administration.

Short-acting Antimuscarinics (SAMA)

• SAMAs are bronchodilators used as alternatives to the beta agonists in asthma therapy.
• SAMAs are short-acting and used "as required" by symptoms and NOT on a regular basis.
• An example of SAMA is Ipratropium Bromide (Atrovent HFA)

Long-acting Antimuscarinics (LAMA)

• LAMAs are given on a regular basis to prevent or reduce symptoms of asthma.
• Combined use of LABA and LAMA can increase the bronchodilation effect.
• Inhalation is preferable to oral administration with LAMAs because it is more effective and provides less systemic side effects

Methylxanthines

• Methylxanthine inhibits intracellular release of calcium, and decreases microvascular leakage into the airway mucosa. Which results in bronchodilation
• Methylxanthine inhibits the late response to allergens.
• Methylxanthines are used for asthma and COPD
• Examples are Theophylline (Nuelin, Theodor) and Aminophylline
• Side effects are headache, vomiting, cardiac arrhythmias, seizures, and aggravation of gastroesophageal reflux.

Methylxanthines (Remarks)

• Methylxanthines are less effective and cause more side effects than beta agonists.
• Individualized dosing is based on serum theophylline levels, using ideal body weight to calculate dose and maintaining levels between 5-15mcg/ml.
• Safer drugs have largely replaced methylxanthines, now used for long-term oral prophylaxis of asthma unresponsive to beta-agonists or inhaled corticosteroids.
• The methylxanthine theophylline is used for long-term control as an adjunct to beta-2 agonists, with additive effect with B2-agonist activity.
• Extended-release theophylline helps manage nocturnal asthma.

Anti-Inflammatory Agents

• Corticosteroids, leukotriene modifiers, mast cell stabilizers, and antihistamines are all anti-inflammatory agents

Corticosteroids

• Steroids reduce inflammation and airway swelling, making it easier to breath

Inhaled Steroids

• For maintenance and preferred drugs for long-term prophylaxis of Asthma and COAD
• Can be combined with Long-acting bronchodilator therapy in more advanced disease
• Corticosteroids may interfere with the balance of normal flora, and induce oral candidiasis
• Rinse mouth after steroid use to reduce the number of pathogens in the mouth and prevent pulmonary infection
• Examples: Beclomethasone (Becotide, Becloforte) inhaler, Budesonide (Pulmicort) inhaler, Fluticasone (Flixotide) inhaler

Oral and Intravenous Steroids

• Steroids reduce inflammation and airway swelling, making it easier to breath
• Steroids reduce inflammation and airway swelling, making it easier to breath

Oral or Intravenous Steroids Indications

• Use for short-term severe acute exacerbations limited to 5-7 days in the hospital.

Oral or Intravenous Steroids Side Effects

• Cushing Syndrome and side effects are involved, meaning the risks may outweigh the benefits
• Examples: PO Prednisolone and IV Hydrocortisone

Drugs for Symptom Relief

• Drugs can be used to treat symptoms like cough and nasal congestion

Cough Mixtures

• Antitussives: Codeine narcotic and Actifed Compound, Promethazine Compound Linctus
• Expectorants: Ammonia and Ipecacuanha Mixture (MES)
• Mucolytics: Acetylcysteine (Fluimucil), Mucosolvan (Ambroxol), Bromhexine (Bisolvon)
• The common cold is a viral infection of the upper respiratory tract that produces many symptoms

Nasal Sprays or Orals

• Nasal Sprays like Naphazoline, Oxymetazoline (Otrivin 安鼻靈), Xylometazoline, Tetrahydrozoline
• Orals like Ephedrine 麻黄碱, Pseudoephedrine 偽麻黃鹼 (Sudafed), Phenylephrine (Neo-synephrine), Phenylpropanolamine

Allergic Rhinitis

• Inflammation of nasal mucosa due to allergens, such as pollens or dust mites.
• Strong genetic predisposition involved An immediate hypersensitivity: Antigen interacts with Immunoglobulin E (IgE), antigen-specific IgE bound on mast cells
• This causes mast cell activation to release inflammatory mediators, including histamine, cytokines, chemokines, and leukotrienes.
• Histamine acts on H1 receptors, increasing vascular permeability/vasodilation, leading to fluid moving into tissues and causing swelling.

Skin

• Erythema, urticaria (hives), skin rash, pruritus

Nasal

• Allergic rhinitis, nasal vasodilation, nasal congestion, runny nose, sneezing

Bronchus

• Increase smooth muscle contraction, bronchospasm/asthma attack
• H-1 receptor antihistamines have anticholinergic properties
• Skin: Reduce skin rash, reduce itchiness.
• Decongenstants: relieve congestion to stop runny nose

Antihistamine Metabolism

• Via the liver

Alpha 1 Adrenergic Agonists

• Alpha 1 Adrenergic Agonisis a1 activate alpha receptors to constrict Respiration

MOA for Alpha 1 Adrenergic Agonists

• Stimulate sympathetic nervous system, resulting in fight or flight response.
• Stimulate nasal vasoconstriction for drying nasal secretions.

Indications and Side Effects for Alpha 1 Adrenergic Agonists

• Inhibit salivation, stop running nose, relieve nasal congestion.
• Side effects include, tachycardia and arrhythmias, pupil dilation, dry mouth.

Oral vs Nasal for Alpha 1 Adrenergic Agonists

• Oral: Ephedrine, Pseudoephedrine, Phenylephrine
• Nasal spray: Naphazoline, Oxymetazoline, Xylometazoline, Tetrahydrozoline

Antittusives: Promethazine Compound Linctus

• Antihistamine.
• Antitussives: Promethazine Compound Linctus
• Compound of Codeine Phosphate, Ephedrine Hydrochloride, Promethazine Hydrochloride.

Codeine

• Opioid. Suppresses cough

Ephedrine

• Acts as an agonist of alpha-1, beta-1 and beta-2-adrenergic receptors.
• Is a decongestant and bronchodilator.
• Works by reducing swelling and constricting blood vessels in the nasal passages and widening the lung airways.

Antitussives: Actifed Compound Linctus

• Actifed is composed of Codeine Phosphate, Pseudoephedrine Hydrochloride, and Triprolidine Hydrochloride to relieve nasal congestion and cough

Codeine (Actifed)

• Opioid. Suppresses cough.

Pseudoephedrine (Actifed)

• Acts mainly as an agonist of alpha-adrenergic receptors and less strongly as an agonist of beta-adrenergic receptors.
• This causes vasoconstriction leading to decongestant effect.
• Pseudoephedrine stimulates heart muscles, whereas pseudoephedrine predominantly facilitates stimulation in the nasal passage.

Triprolidine (Actifed)

• An antihistamine which treats sneezing, runny nose, itchy nose and throat, and itchy/watery eyes due to allergies

Antitussives

• Codeine (narcotic antitussives) suppresses the cough reflex and has a sedative effect, but may cause light-headedness, drowsiness, dizziness, tachycardia, orthostatic hypotension, nausea, constipation, and dependence.
• Avoid driving and be aware of the risk of addiction when considering

Dextromethorphan

• A cough suppressant for a dry cough that can cause drowsiness, dizziness, and constipation.
• Avoid driving

Nursing Considerations for Antiussives

• Avoid driving and operating machinery when taking such medications due to sedative effects.
• Avoid combining with alcohol or depressants
• Increase fluid intake in warm water and maintain a cool, humid environment
• Change positions slowly to reduce the risk of orthostatic hypotension
• Get education including their side effects from your doctor
• Avoid prolonged use to prevent overdose and dependence
• Consult provider if coughing persists over a week
• Immediately report series respiratory effects
• Codeine is contraindicated for all patients 12 years or younger

Expectorants

• Used to reduce viscosity of bronchial secretion, which are discharged via coughing
• Can cause, gastrointestinal upset, nausea, vomiting, headache, dizziness, sleepiness, and drowsiness.

Examples of Expectorants

• Includes, Guaifenisin/Mucinex, Cocillana, Ammonia and Ipecacuanha Mixture (MES)
• Increase fluid intake

Mucolytics

• These agents liquefy secretions and breakdown mucus plugs
• This can yield side effects like dizziness, drowsiness, nausea, vomiting, skin rash, and stomatitis (inflammation of mouth and lips)

Bromhexine (Bisolvon)

• Mucolytic agent that acts on mucus glands in the respiratory tract to change bronchial secretions.
• It Reduces mucus viscosity and increases cilia activity to clean the tract

Mucosolvan

• As tablet for oral use

Acetylcysteine

• Serves to decrease mucus viscosity by breaking down mucus build up
• It can be taken Orally as granules as well as effervescent tabs
• Insure proper fluid intake
• Make sure patients receive education on effective coughing techniques
• Administer techniques to deal with powder form

Nursing Consdierations

• Teach patients proper techniques when using medical apparatus like masks and dry powder inhalers

Ways to Prevent Bronchospasm

• Keep away from other irritants
• Quit smoking
• Consult for bronchodilators prior to exercise
• When treating respiratory patients, monitor therapeutic effects of prescribed drugs. If severe, the respiratory complication may elevate to medical emergency that may need immediate attendance
• Note side effects of most bronchodilators
• Have them rinse their with water after use of the apparatus to prevent dryness of the mouth and infection relating to such side effects

Explore the most effective medications for quickly relieving acute bronchospasm and the mechanisms of action of asthma drugs. Learn about potential side effects associated with certain medications. Test your knowledge of asthma treatments.