The first B2-receptor agonist ever developed, salbutamol was originally marketed and sold in 1968 under the brand name Ventolin® for the treatment of asthma. Although the medication may be given intravenously, it is generally more convenient to administer it by inhalation in a nebulizer or metered dose inhaler, permitting the drug to exert its bronchial smooth muscle relaxing effects within five to 20 minutes of use. Since its development, the drug has been employed as a treatment for cystic fibrosis, congenital myasthenic syndromes, and exercise-induced brochospasm as well as to delay premature labor. There is considerable variability in patient response to the drug, resulting in large variances in the salbutamol dosage needed for effective relief of symptoms among patients. When administering this medication, factors like the patient's age, condition, form of the medication, medical history, and drug regimen need to be figured into dose calculations.
When giving the medication by inhalation for the prevention of bronchospasm, the average recommended salbutamol dosage is two puffs every four to six hours as required. As of 2011, the medication has not been shown to provide any additional risks to children under four years of age, nor has it been proven to be safe or effective in this population. The appropriate salbutamol dosage for asthma prevention in children under four must be carefully established on an individual basis.
The safety and efficacy of salbutamol in solution form administered using a nebulizer has been found to be safe and effective in children over the age of two. These patients should receive between 0.63 and 1.25 mg of the solution three or four times per day as required, up until the age of 12. The appropriate salbutamol dosage for children younger than two should again be cautiously assessed according to individual patient needs, beginning with the lowest possible dose and increasing this dose only under close medical supervision. Patients over the age of 12 who continue to use the drug in solution form generally receive 2.5 mg three or four times daily.
Patients who are being treated for bronchospasm associated primarily with exercise do not need to take the medication several times each day. Instead, it may be given 15 to 30 minutes before activity. These patients should take two puffs of the drug in its aerosolized form unless they are under four years of age. Patients under four may not require as high an initial dose for effective bronchospasm prevention.
Elderly patients may also require careful supervision when adjusting their salbutamol dosage. Due to the increased risk of heart or kidney problems in geriatric patients, smaller increments should be used when increasing the dose. A number of different medications may also interact with salbutamol. While it is not generally recommended to use medications that interact with this drug, it may be necessary to do so for effective control of symptoms. If incorporating a drug that could interact with a patient's treatment regimen, the salbutamol dosage may need to be adjusted to compensate.