Is it safe to take magnesium glycinate 120 mg daily while on losartan?

Safety of Magnesium Glycinate with Losartan

Yes, you can safely take magnesium glycinate 120 mg daily while on losartan, and this combination may actually provide additional blood pressure benefits without significant drug interactions.

No Direct Drug Interaction

• Losartan does not have clinically significant interactions with magnesium supplementation, as the major metabolic pathways for losartan (CYP3A4, 2C9, and 2C10) are not affected by magnesium. 1
• The pharmacokinetics of losartan remain linear and dose-proportional without interference from mineral supplements like magnesium. 1

Potential Cardiovascular Benefits of Combined Therapy

• Magnesium supplementation (500-1000 mg/day) can reduce blood pressure by as much as 5.6/2.8 mm Hg, and importantly, magnesium increases the effectiveness of all antihypertensive drug classes including angiotensin receptor blockers like losartan. 2
• Your dose of 120 mg magnesium glycinate is well below the therapeutic range studied for blood pressure reduction, making it unlikely to cause excessive hypotension when combined with losartan. 2
• Magnesium acts as a natural calcium channel blocker, increases nitric oxide production, and improves endothelial function—mechanisms that complement losartan's angiotensin-II blocking effects. 2, 3

Important Monitoring Considerations

• Monitor for symptoms of hypotension (dizziness, lightheadedness, fatigue), especially during the first few weeks of combined therapy, as both agents can lower blood pressure. 4
• Check your blood pressure regularly at home; a reading ≥135/85 mm Hg at home corresponds to office hypertension ≥140/90 mm Hg. 5
• Have your serum potassium and creatinine checked within 1-2 weeks if you're also taking other medications that affect electrolytes, though magnesium glycinate at this dose is unlikely to cause hyperkalemia. 5

Zinc Depletion Caveat

• Be aware that losartan itself increases urinary zinc excretion and can induce zinc deficiency over time (urinary zinc/creatinine ratio increased from 0.020 to 0.034 μg/mg with losartan alone). 6
• If you're taking losartan long-term, consider monitoring zinc status or adding a zinc supplement (15-30 mg daily), as this is a more relevant mineral concern than magnesium with losartan therapy. 6

Practical Algorithm for Safe Use

1. Start the magnesium glycinate 120 mg daily at any time of day (losartan can be taken without regard to food or timing). 1
2. Monitor blood pressure at home for the first 2 weeks to ensure no excessive drop below your target of <130/80 mm Hg. 5
3. Watch for hypotension symptoms such as dizziness upon standing, especially if you're elderly or taking other blood pressure medications. 5
4. Continue routine monitoring of potassium and creatinine as recommended by your physician (typically every 2-4 weeks after any medication changes, then annually). 5

When to Avoid This Combination

• If you have baseline hypotension (systolic BP <90 mm Hg) or symptomatic orthostatic hypotension, delay adding magnesium until blood pressure is stable. 4
• If you develop severe diarrhea from magnesium supplementation, this could lead to dehydration and worsen hypotension risk with losartan. 2