Salbutamol

Indications

Salbutamol is used for: Acute severe asthma, Severe bronchospasm

Adult Dose

Oral Acute bronchospasm Adult: 2-4 mg 3 or 4 times daily, up to 8 mg 3 or 4 times daily. As modified-release tab: 8 mg bid. Not to exceed 32 mg/day Elderly: 2 mg 3 or 4 times daily. Inhalation Acute bronchospasm, Intermittent episodes of asthma Adult: As metered-dose aerosol or dry powd inhaler (90 or 100 mcg/actuation): 1 or 2 inhalations (1 ConviCap) as a single dose when required. Not to exceed 12 inhalations/24 hr Chronic maintenance or prophylactic therapy Adult: As metered-dose aerosol or dry powd inhaler (90 or 100 mcg/actuation): 2 inhalations (1 ConviCap) 3-4 times daily. Max: 800 mcg daily. Acute severe asthma Adult: As metered-dose inhaler (100 mcg/actuation) via spacer device: Initially, 4-8 puffs inhaled every 20min for up to 4 hr and then 1-4hrly as required. Max: 10 inhalations. Prophylaxis of exercise-induced bronchospasm Adult: As metered-dose aerosol or dry powd inhaler (90 or 100 mcg/actuation): 2 inhalations (1 ConviCap) 10-15 min prior to exercise. Nebuliser Solution Severe bronchospasm Adult: Via nebuliser: 2.5-5 mg, up to 4 times daily, alternatively, may be given continuously at a rate of 1-2 mg/hr. Reconstitution: Dilute 0.5 mL of soln to a total of 3 mL w/ NaCl 0.9% to prepare a 2.5 mg dose. Respirator Solution 0.5-1.0 ml should be diluted to final volume of 3-4 ml with normal saline for injection. The resulting solution is inhaled from a suitably driven nebulizer until aerosol generation ceases. Should take about 10 minutes. Parenteral Severe bronchospasm Adult: IM/SC: 500 mcg (8 mcg/kg) and repeated 4 hrly as required. Intravenous Severe bronchospasm Adult: As 50 mcg/mL soln: 250 mcg (4 mcg/kg) injected slowly. May be repeated if necessary. As 10 mcg/mL soln: Usual rate of 3-20 mcg/min (0.3-2 mL/min), adjusted according to patient needs. Higher doses may be used in resp failure. Reconstitution: Dilute 5 mL of soln w/ 500 mL NaCl or dextrose inj or other suitable diluents to provide a 10 mcg/mL soln.

Child Dose

Oral Children Acute bronchospasm Tablet Child: 2-6 yr 1-2 mg; >6-12 yr 2 mg; >12 yr 2-4 mg 3 or 4 times daily, up to 8 mg 3 or 4 times daily. Syrup 2 - 6 years: 2.5 ml syrup, 3-4 times daily 6-12 years: 5 ml syrup, 3-4 times daily Over 12 years: 5-10 ml syrup, 3-4 times daily (2-4 mg tablet, 3-4 times daily) Inhalation Acute bronchospasm Child: 4-12 yr 1 inhalationas a single dose, may be increased to 2 inhalations as necessary. Max: 400 mcg daily. Prophylaxis of exercise-induced bronchospasm Child: 4-12 yr 1 inhalation 10-15 min prior to exercise. Nebuliser Solution Severe bronchospasm Child> 4 years: Via nebuliser: 2.5-5 mg, up to 4 times daily, alternatively, may be given continuously at a rate of 1-2 mg/hr. Reconstitution: Dilute 0.5 mL of soln to a total of 3 mL w/ NaCl 0.9% to prepare a 2.5 mg dose. Respirator Solution 0.5-1.0 ml should be diluted to final volume of 3-4 ml with normal saline for injection. The resulting solution is inhaled from a suitably driven nebulizer until aerosol generation ceases. Should take about 10 minutes. Parenteral Severe bronchospasm Child >12 years: IM/SC: 500 mcg (8 mcg/kg) and repeated 4 hrly as required. Intravenous Severe bronchospasm Child >12 years: As 50 mcg/mL soln: 250 mcg (4 mcg/kg) injected slowly. May be repeated if necessary. As 10 mcg/mL soln: Usual rate of 3-20 mcg/min (0.3-2 mL/min), adjusted according to patient needs. Higher doses may be used in resp failure. Reconstitution: Dilute 5 mL of soln w/ 500 mL NaCl or dextrose inj or other suitable diluents to provide a 10 mcg/mL soln.

Renal Dose

Administration

Tablet/Syrup: Should be taken on an empty stomach. Take 1 hr before or 2 hr after meals. Aerosol Metered-Dose Inhaler Prime the inhaler before using for the first time and in cases where the inhaler has not been used for >2 weeks by releasing 4 “test sprays” into the air, away from the face Patient instructions for administration Shake well before each use Breathe out fully through the mouth, expelling as much air from your lungs as possible; place the mouthpiece fully into the mouth, holding the inhaler in its upright position and close the lips around it While breathing in deeply and slowly through the mouth, fully depress the top of the metal canister with your index finger Hold your breath as long as possible, up to 10 seconds; before breathing out, remove the inhaler from your mouth and release your finger from the canister If your physician has prescribed additional puffs, wait 1 minute, shake the inhaler again, and repeat steps listed above; replace the cap after use Cleaning To maintain proper use of this product, it is important that the mouthpiece be washed and dried thoroughly at least once a week Keeping the plastic mouthpiece clean is very important to prevent medication buildup and blockage The inhaler may cease to deliver medication if not properly cleaned and air dried thoroughly If the mouthpiece becomes blocked, washing the mouthpiece will remove the blockage Powder Metered-Dose Inhaler Does NOT require priming Do not use with a spacer or volume holding chamber Cleaning Keep clean and dry at all times Never wash or put any part of inhaler in water Routine maintenance not required If the mouthpiece needs cleaning, gently wipe with a dry cloth or tissue as needed

Contra Indications

Salbuatmol inhaler is contraindicated in patients with a history of hypersensitivity to any of its components. Although intravenous Salbutamol, and occasionally Salbutamol tablets, is used in the management of premature labour uncomplicated by conditions such as placenta praevia, ante-partum haemorrhage or toxaemia of pregnancy, Salbutamol inhaler preparations are not appropriate for managing premature labour. Salbutamol preparation should not be used for threatened abortion during the first or second trimesters of pregnancy.

Precautions

Hyperthyroidism, myocardial insufficiency, arrhythmias, susceptibility to QT-interval prolongation, HTN, DM, glaucoma, hypokalaemia, seizure disorder. Renal impairment. Elderly. Pregnancy and lactation. Monitoring Parameters Monitor BP, heart rate, electrolyte and fluid balance; glucose, lactate and K levels. Lactation: Unknown whether drug is excreted in milk; not recommended

Pregnancy-Lactation

Pregnancy There are no randomized clinical studies of use during pregnancy Available data from published epidemiological studies and postmarketing case reports of pregnancy outcomes following inhaled albuterol use do not consistently demonstrate a risk of major birth defects or miscarriage In animal reproduction studies, when administered SC to pregnant mice there was evidence of cleft palate at ?9x the maximum recommended human daily inhalation dose (MRHDID) Clinical considerations Disease-associated maternal and/or embryo/fetal risk In women with poorly or moderately controlled asthma, there is an increased risk of preeclampsia in the mother and prematurity, low birth weight, and small for gestational age in the neonate Closely monitor pregnant women and adjust medications as necessary to maintain optimal control Labor or delivery Because of potential for beta-agonist interference with uterine contractility, restrict use for relief of bronchospasm during labor to those patients in whom the benefits clearly outweigh the risk Lactation There are no available data on the presence of albuterol in human milk, the effects on the breastfed child, or the effects on milk production Consider developmental and health benefits of breastfeeding along with mother’s clinical need for therapy and any potential adverse effects on breastfed child from drug or from underlying maternal condition

Interactions

Diuretics, corticosteroids and xanthines may augment hypokalaemia. CV effects potentiated by MAOIs, TCAs, sympathomimetics. Increases absorption of sulfamethoxazole when used together. May markedly increase heart rate and BP when used with atomoxetine. Reduces serum levels of digoxin. Hypokalaemia induced by salbutamol increases the risk of digitalis toxicity. BP should be closely monitored if linezolid is used concurrently with salbutamol.

Side Effects

Side effects of Salbutamol : >10% Tremor (20%), Nervousness in children aged 2-6 years (20%), Insomnia in children aged 6-12 years receiving 4-12 mg q12hr (11%) 1-10% Nausea (10%), Fever (1.6-9%), Bronchospasm (8%), Vomiting (7%), Headache (4-7%), Dizziness (1-7%), Cough (5%), Allergic reactions (4%), Otitis media (3.3%), Epistaxis in children (3%), Increased appetite (3%), Urinary tract infection (3%), Dry mouth (<3%), Eructation or flatulence (<3%), Increased sweating (<3%), Pain (2.7%), Dyspepsia (1-2%), Hyperactivity (1-2%), Chills (<2%), Lymphadenopathy (<2%), Ocular pruritus (<2%), Sweating (<2%), Conjunctivitis in children aged 2-6 years (1%), Dysphonia (>1%), Flu syndrome, Nervousness <1% Epigastric pain, Epistaxis in adults, Hyperactivity in children Frequency Not Defined Adverse reactions such as hypertension, angina, vertigo, central nervous system stimulation, insomnia, headache, metabolic acidosis, and drying or irritation of oropharynx Hypersensitivity, Hypokalemia, Increased blood glucose levels, Prolonged QT interval and ST-segment depression, Sleeplessness, Tachycardia (incidence varies with formulation) Urticaria, angioedema, rash, bronchospasm, and oropharyngeal edema (rare) Potentially Fatal: Potentially serious hypokalaemia after large doses.

Mode of Action

Salbutamol is a direct-acting sympathomimetic with beta-adrenergic activity and selective action on ?2 receptors, producing bronchodilating effects. It also decreases uterine contractility.