Terbutaline
Chemical
Enthanolamine derivative bronchodilator with tocolytic activities
Use
Uterine Hypercontractility (>5 contractions in 10 mins)
Presentation
5ml ampoule (5mg/5ml)
Dose
Draw up 25mcg/ml
Give IV 50mcg boluses up to 250mcg in total
Route
IV
Onset
Immediate
MoA
Selective b2 agonist
Preferential for B2 receptors on bronchial, vascular & uterine smooth muscles
PD
Relaxes smooth muscle and inhibits uterine contractions
PK
A
D
25% PPB
M
Liver CYP450
E
T1/2b 11-16hrs
90% excreted in urine unchanged
Adverse Effects
Foetal & maternal tachycardia
Foetal hypoglycaemia
Maternal hypotension
Tremor
HA
Nervousness
Arrythmia, tachycardia, palpitations
Muscle cramps
Hypokalaemia
Hyperglycaemia
C/I
IHD
HTN
Hyperthyroidism