Hypertension in Pregnancy Drug Summary

• GI effects (GI upset which may be minimized with food and with use of enteric-coated formulation, GI irritation like erosion, ulceration); Hematologic effects (increase in bleeding time, decrease in platelet adhesiveness, hemorrhage); hypersensitivity reactions

• Contraindicated in patients with active pathological bleeding (eg peptic ulcer, intracranial hemorrhage), known allergy, hemophilia, hemorrhagic disorders, severe renal or hepatic impairment, third-trimester pregnancy
• Ensure benefit outweighs the risk before using with drugs that increase risk of bleeding (eg thrombolytics, NSAIDs)

Adverse Reactions

• Based on serum Mg levels
  • Serum Mg >1.2 mmol/L (3 mg/dL): Depressed CNS; GI effect (diarrhea); Depressed neuromuscular functions
  • Serum Mg >2.1 mmol/L (5 mg/dL): CNS effect (somnolence); CV effect (flushing)
  • Serum Mg >5.1 mmol/L (12.5 mg/dL): CV effect (complete heart block); Respiratory effect (respiratory depression)

• Monitor blood pressure
• Monitor serum Mg and patient for signs of hypermagnesemia to avoid overdose
  • Monitor for diarrhea, oliguria, arrhythmias, hypotension, absent or decreased deep tendon reflex, respiratory and CNS depression when administering rapidly by IV
• Monitor fetal heart rate
• Avoid in patients with heart block or severe renal failure and do not administer within 2 hours of delivery
• Use with caution in less severe renal impairment and in myasthenia gravis patients

• Serum osmolarity and hypernatremia

• Use with caution in patients with cirrhosis, edema, heart failure, renal impairment
• Avoid in patients with respiratory and metabolic alkalosis, hypernatremia, or hypokalemia

• CV effects (orthostatic hypotension, heart failure, bradycardia; rarely heart block); CNS effects (headache, dizziness, mild paresthesia); GI effects (nausea/vomiting, diarrhea, dyspepsia); Rare hepatic effects (elevated LFT, jaundice, hepatitis); Other effects (nasal congestion, dyspnea, muscle weakness, tremor)

• Contraindicated in severe bradycardia, pre-existing high-degree AV block, cardiogenic shock, uncompensated heart failure, obstructive airway disease (eg bronchial asthma)
• Use with caution in patients with bronchospastic diseases, hepatic impairment, 1st-degree heart block, inadequate cardiac function, peripheral vascular disease and patients on insulin
• Beta-blockers may mask the symptoms of hyperthyroidism and hypoglycemia and may aggravate psoriasis
• Patients on long-term treatment should not discontinue abruptly; should discontinue gradually over 1-2 weeks
• Monitor blood pressure while administering IV Labetalol
  • May cause postural hypotension, administer dose to patient while supine and patient should remain supine for 3 hours
  • Withdraw in patients if they develop signs of liver impairment

• CV effects (reflex tachycardia, hypotension); CNS effects (headache, dizziness); Other effects (flushing, nausea/vomiting, tocolysis, myalgia, polyuria, dyspnea, nocturia, hypokalemia)

• Avoid in patients with advanced aortic stenosis, unstable angina, cardiogenic shock, acute angina attack
• Closely monitor patients with hepatic or renal impairment, angina, or heart failure
• Discontinue infusion if unacceptable hypotension or tachycardia occurs

• CV effects (depression of cardiac function, hypotension, worsening heart failure, edema, flushing, tachycardia); GI effect (constipation); CNS effects (headache, dizziness); Other effects (rashes, fever, abnormal liver function, gingival hyperplasia, myalgia, tremor)
• May cause paradoxical increase in ischemic or transient blindness
• May cause postpartum decrease in milk volume and lactation suppression

• Use with caution in hypotension, whose cardiac reserve is poor and in heart failure
• Use with caution when administered with Magnesium sulfate
• Contraindicated in cardiogenic shock, aortic stenosis, recent acute MI, acute stable angina, or other known atherosclerotic CV disease

• Most adverse effects are transient or reversible
• CNS effects (drowsiness, dizziness, headache, weakness, fatigue, disturbed sleep, paresthesia, depression); CV effects (orthostatic hypotension, edema, angina); GI effects (nausea/vomiting, diarrhea, constipation, rarely pancreatitis, colitis or sore tongue); Hematologic effects (thrombocytopenia, leukopenia, hemolytic anemia and granulocytopenia have occurred)

• Avoid in patients with active liver disease; concomitant use of monoamine oxidase inhibitors
• Use with caution in patients with impaired renal or hepatic function, history of hemolytic anemia, history of liver disease or depression, and patients with parkinsonism
• Monitor blood pressure, blood counts, liver enzymes, direct Coombs’ test

• Typically subside with continued therapy: CNS effect (dizziness); CV effects (tachycardia, palpitations, angina, flushing); GI effects (anorexia, nausea/vomiting, diarrhea); Respiratory effect (nasal congestion)
• Other CV effects (postural hypotension, fluid retention, edema); Other effects (weight gain, tremor, conjunctivitis, muscle cramps, lacrimation)
• Less common: Pyridoxine depletion with resulting peripheral neuropathy; Hematologic effects (blood dyscrasia, hemolytic anemia); Hypersensitivity reactions; can also cause a condition resembling SLE

• Avoid in patients with severe tachycardia, heart failure with high cardiac output, dissecting aortic aneurysm, cor pulmonale, or myocardial insufficiency due to mechanical obstruction, idiopathic SLE and related disorders
• Use with caution in patients with ischemic heart disease, recent MI, heart failure, impaired renal or hepatic function
• CBC, antinuclear antibody determinations and urinalysis should be done periodically during long-term therapy

• Adverse effects are typically either due to hypotensive effects or from excessive cyanide accumulation
• These effects may be reduced with a decrease in infusion rate: GI effects (nausea/vomiting, abdominal pain); CNS effects (apprehension, headache, dizziness, restlessness); CV effects (retrosternal discomfort, palpitations); Other effects (perspiration, muscle twitching)
• Excessive cyanide may result in tachycardia, sweating, hyperventilation, arrhythmias and metabolic acidosis; methemoglobinemia may also occur
• Thiocyanate may cause tinnitus, miosis, hyperreflexia, confusion, hallucinations and convulsions

• Blood pressure and acid-base balance should be monitored closely
• Avoid extravasation
• Avoid in compensatory hypertension
• Use with caution or not at all in hepatic impairment and in patients with low plasma cobalamin concentration or Leber’s optic atrophy
• Use with caution in patients with impaired cerebrovascular circulation, patients with hypothyroidism