Magnesium

Question 1

Magnesium - Class (3)

Answer 1

• electrolyte- CNS depressant- anticonvulsant

Question 2

Magnesium - Actions (3)

Answer 2

• (anticonvulsant) Tx/prophylaxis of sz due to toxemia of pregnancy (eclampsia) - reduces chance of post infarction ventricular arrhythmias by increasing membrane stability and decreasing ventricular excitability- may result in relaxation of bronchial and vascular smooth muscle which is probably secondary to Ca blockade

Question 3

Magnesium - Indications (7)

Answer 3

• refactory VF/VT- Torsades de pointes- refractory sz related to hypomag in alcoholics- eclampsia- hyper-reflex of toxemia of pregnancy (pre-eclampsia)- cardiac arrhythmias due to dig toxicity- controversial: refractory bronchospasm not responsive to Beta agonist/steroid/aminophyline

Question 4

Magnesium - Contraindications (2)

Answer 4

• heart block- controversy in acute MI pt

Question 5

Magnesium - Side Effects (2)

Answer 5

• Rapid admin: flushing/hypotension/sweating/mild bradycardia- Hypermagnesemia: may produce depressed reflexes, flaccid paralysis, circulatory collapse, respiratory depression/paralysis, and diarrhea

Question 6

Magnesium - Precautions (3)

Answer 6

• monitor respiratory rate due to resp. depression side effect- IV CaCh available as antagonist- concurrent use w/ CNS depressant req lower dosage