ritodrine hydrochloride

(ri' toe dreen)

Pregnancy Category B

Drug classes

Therapeutic actions

A β-receptor agonist that acts relatively selectively to inhibit contractility of uterine smooth muscle.




Available Forms: Injection--10, 15 mg/mL; injection in 5% Dextrose--0.3 mg/mL

Individualize dosage by balancing uterine response and unwanted effects. The following is a guide to safe and effective dosage.


0.05 mg/min IV initially (0.33 mL/min or 20 drops/min using a microdrip chamber at the recommended dilution; see below). Gradually increase by 0.05 mg/min (10 drops/min) every 10 min until desired result is attained. Usual effective dosage is between 0.15 and 0.35 mg/min (30---70 drops/min) continued for at least 12 h after uterine contractions cease.


OralVaries30---60 min

Metabolism: Hepatic, T1/2: 1.7---2.6 h

Distribution: Crosses placenta; enters breast milk

Excretion: Urine

IV facts

Adverse effects

Maternal Effects

Fetal Effects

Clinically important interactions

Nursing Considerations


History: Hypersensitivity to ritodrine or components of preparation, pregnancy, antepartum hemorrhage, eclampsia and severe preeclampsia, intrauterine fetal death, chorioamnionitis, maternal cardiac disease, pulmonary hypertension, maternal hyperthyroidism, uncontrolled maternal diabetes mellitus, hypovolemia, cardiac arrhythmias, uncontrolled hypertension, pheochromocytoma, bronchial asthma already treated by betamimetics or steroids
Physical: Maternal and fetal heart rate, maternal BP and R, plasma glucose and electrolytes (potassium)


Drug-specific teaching points

Adverse effects in Italic are most common; those in Bold are life-threatening.