ADVERSE REACTIONS On rare occasion oral administration of the drug has been associated in time with the occurrence of hypotension, tachycardia, chest pain, nausea, vomiting, dizziness, abdominal distress, and severe rash. If rash appears, the drug should be discontinued. Although available evidence suggests a temporal association of these reactions with isoxsuprine, a causal relationship can be neither confirmed nor refuted. β-Adrenergic receptor stimulants such as isoxsuprine hydrochloride have been used to inhibit pre-term labor. Maternal and fetal tachycardia may occur under such use. Hypocalcemia, hypoglycemia, hypotension and ileus have been reported to occur in infants whose mothers received isoxsuprine. Pulmonary edema has been reported in mothers treated with β-stimulants. Vasodilan (isoxsuprine HCl tablets, USP) is neither approved nor recommended for use in the treatment of premature labor.