orciprenaline

orciprenaline

see metaproterenol.

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metaproterenol sulfate (orciprenaline)

Alupent

Pharmacologic class: Sympathomimetic, selective beta₂-adrenergic agonist

Therapeutic class: Bronchodilator

Pregnancy risk category C

Action

Relaxes beta₂ (pulmonary) receptors, causing bronchodilation and inhibiting histamine release. Acts on beta₁ (cardiac) receptors with weaker effect.

Availability

Aerosol solution for inhalation: 0.65 mg/metered spray

Nebulizer inhaler: 0.4%, 0.6%

Syrup: 10 mg/5 ml

Tablets: 10 mg, 20 mg

⊘Indications and dosages

➣ Bronchial asthma and reversible bronchospasm

Adults and children ages 9 and older or weighing more than 27 kg (59.5 lb): 20 mg P.O. three or four times daily

Children ages 6 to 9 or weighing less than 27 kg (59.5 lb): 10 mg P.O. three or four times daily

Aerosol solution for inhalation -

Adults and children ages 12 and older: Two or three inhalations by metered aerosol (1.3 or 1.9 mg) q 3 to 4 hours, to a maximum of 12 inhalations (7.8 mg) in 24 hours. Alternatively, one plastic ampule of 0.4% or 0.6% solution for nebulization by intermittent positive-pressure breathing device (usually not given more than q 4 hours).

Contraindications

• Hypersensitivity to drug or its components
• Tachyarrhythmias

Precautions

Use cautiously in:
• unstable vasomotor system disorders, hypertension, coronary artery disease, peripheral or mesenteric vascular thrombosis, hyperthyroidism, chronic obstructive pulmonary disease complicated by degenerative heart disease, hypoxia, hypercapnia
• history of cerebrovascular accident or seizure disorders
• patients who've received general anesthesia
• labor and delivery
• pregnant or breastfeeding patients.

Administration

• If patient is using aerosol metered-dose inhaler, place mouthpiece well into his mouth and have him close lips tightly around it. Tell him to exhale completely through nose and then inhale slowly and deeply through mouth while activating inhaler. Have him hold his breath for a few seconds and then remove mouthpiece and exhale slowly. Wait about 2 minutes between inhalations. Rinse mouthpiece with water after use.
• Know that use of Aero-Chamber may aid proper drug delivery.

Route	Onset	Peak	Duration
P.O.	15 min	1 hr	4 hr or more
Inhalation (aerosol)	1 min	1 hr	4 hr or more
Inhalation (nebulizer)	5-30 min	Unknown	4 hr or more

Adverse reactions

CNS: drowsiness, tremor, vertigo, headache, nervousness, restlessness, apprehension, anxiety, fear, CNS stimulation, hyperkinesia, insomnia, irritability, weakness

CV: tachycardia, hypertension, palpitations, anginal pain, cardiac arrest (with excessive use)

GI: nausea, vomiting, diarrhea, heartburn, dry mouth

Respiratory: cough, respiratory difficulty, bronchospasm, pulmonary edema, paradoxical bronchiolar constriction (with excessive use)

Skin: rash, sweating, pallor, flushing

Other: abnormal or bad taste, hypersensitivity reaction

Interactions

Drug-drug. Epinephrine, other sympathomimetics: increased risk of arrhythmias

MAO inhibitors, tricyclic antidepressants: potentiation of metaproterenol effects

Propranolol and other beta-adrenergic blockers: inhibition of bronchodilating effect

Patient monitoring

☞ Monitor patient for hypersensitivity reaction or paradoxical bronchospasm. If either occurs, discontinue drug immediately and implement alternative therapy and airway control measures.
• Monitor patient for effective use of aerosol inhaler or hand-held nebulizer.
• Assess for drug efficacy. Be aware that efficacy may decrease with prolonged use.
• Check for adverse effects.

Patient teaching

• Tell patient to take tablets with food if GI distress occurs.
• Teach patient proper use of metered-dose aerosol inhaler.
• Advise patient to remove canister and wash mouthpiece frequently.
☞ Caution patient not to increase number or frequency of inhalations without prescriber's consent; cardiac arrest may occur with excessive use.
• If patient uses multiple drugs to control asthma, assess level of understanding regarding administration. Tell him to continue taking each drug as prescribed even if he feels better.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs mentioned above.