Risks of Terbutaline Use
Terbutaline carries significant cardiovascular, metabolic, and neurological risks including tachycardia, tremors, hypokalemia, hyperglycemia, and potential for seizures, which require careful monitoring and appropriate patient selection.
Cardiovascular Risks
- Terbutaline can produce clinically significant cardiovascular effects including increased heart rate, changes in blood pressure, and symptoms of cardiovascular distress 1
- ECG changes may occur, including flattening of the T wave, prolongation of the QTc interval, and ST segment depression 1
- Maternal tachycardia is the most common side effect, occurring in up to 95.1% of patients receiving terbutaline for preterm labor 2
- Terbutaline should be used with caution in patients with cardiovascular disorders, especially coronary insufficiency, cardiac arrhythmias, and hypertension 1
- The drug can increase systolic blood pressure while decreasing diastolic pressure, creating potential hemodynamic concerns 3
Metabolic Effects
- Terbutaline can cause significant hypokalemia through intracellular potassium shifting, which has potential to produce adverse cardiovascular effects 1
- Hyperglycemia may occur, and large doses of terbutaline have been reported to aggravate pre-existing diabetes mellitus and ketoacidosis 1
- The ECG changes and/or hypokalemia can be acutely worsened when terbutaline is co-administered with non-potassium-sparing diuretics 1
Neurological Risks
- There have been rare reports of seizures in patients receiving terbutaline 1
- Case reports document focal seizures in children after terbutaline administration 4
- Other neurological side effects include tremors, agitation, and headache 5
Pregnancy-Related Risks
- Terbutaline crosses the placenta, with umbilical blood levels ranging from 11% to 48% of maternal blood levels 1
- In pregnant women, terbutaline can cause increased maternal heart rate, transient hyperglycemia, hypokalemia, cardiac arrhythmias, pulmonary edema, and myocardial ischemia 1
- Fetal/neonatal risks include increased fetal heart rate and neonatal hypoglycemia 1
- Terbutaline has not been approved and should not be used for prolonged tocolysis (beyond 48-72 hours) 1
- Animal studies show that rat offspring exhibit alterations in behavior and brain development when dams were treated with terbutaline during late pregnancy and lactation 1
Drug Interactions
- Concomitant use with other sympathomimetic agents is not recommended due to potential deleterious effects on the cardiovascular system 1
- Terbutaline should be administered with extreme caution to patients being treated with monoamine oxidase inhibitors or tricyclic antidepressants 1
- Beta-blockers can block the pulmonary effects of terbutaline and may produce severe bronchospasm in asthmatic patients 1
Respiratory Considerations
- Asthma may deteriorate acutely over hours or chronically over days when using terbutaline 1
- Increased need for terbutaline doses may indicate destabilization of asthma requiring reevaluation and consideration of anti-inflammatory treatment 1
- Immediate hypersensitivity reactions and exacerbations of bronchospasm have been reported after terbutaline administration 1
Risk Mitigation Strategies
- For preterm labor treatment, using glucose as the infusion medium instead of sodium chloride can reduce side effects 6
- Using concentrated solutions helps avoid fluid overload 6
- Careful patient monitoring and immediate reduction or cessation of infusion if severe side effects appear is essential 6
- In asthma treatment, terbutaline should be used with caution in patients with hyperthyroidism, diabetes mellitus, convulsive disorders, or those unusually responsive to sympathomimetic amines 1
When using terbutaline, clinicians must weigh these risks against the potential benefits for each specific indication, with particular caution in pregnant women, patients with cardiovascular conditions, and those with metabolic disorders.