Your Patients Can't Find Magnesium Chloride — Here's How You Can Help

When patients struggle to fill a magnesium prescription or locate the specific supplement they need, they often turn to their provider for answers. With injectable Magnesium Chloride experiencing intermittent shortages since 2023 and oral formulations occasionally hard to find at specific pharmacies, providers are fielding more of these questions than ever.

This guide offers practical steps you can integrate into your clinical workflow to help patients access Magnesium Chloride — or a suitable alternative — with minimal disruption to their treatment.

Current Availability Overview

As of early 2026, the supply picture looks like this:

• Injectable Magnesium Chloride (200 mg/mL): Intermittent shortage. Availability varies by wholesaler and region. Magnesium Sulfate injection is the primary substitute in clinical settings.
• Oral delayed-release tablets (Slow-Mag, generics): Generally available at $8-$25 per 60-count bottle. Stockouts occur at individual pharmacies due to elevated demand.
• Oral capsules, liquids, and supplement forms: Widely available through pharmacy retail and online channels.

Why Patients Can't Find Magnesium Chloride

Understanding the barriers your patients face helps you provide better guidance:

• Pharmacy-level stockouts: Chain pharmacies share supply chains. When a distributor runs low, multiple stores in a region may be affected simultaneously.
• Brand loyalty: Many patients specifically seek Slow-Mag because they're familiar with it. They may not know that generic Magnesium Chloride tablets are therapeutically equivalent.
• Confusion about OTC status: Patients with prescriptions may not realize they can purchase oral Magnesium Chloride over the counter while waiting for their prescription to be filled.
• Injectable-to-oral cascade: Hospital demand for injectable magnesium can indirectly affect oral supplement availability as facilities stock up on alternatives.
• Geographic variation: Supply levels differ significantly between urban and rural areas, and between different pharmacy chains.

5 Steps Providers Can Take to Help Patients

Step 1: Direct Patients to Medfinder

The most efficient way to help patients find Magnesium Chloride is to recommend Medfinder. This tool allows patients to search for real-time pharmacy availability in their area. You can:

• Include the Medfinder link in your after-visit summary
• Have your MA or front desk mention it when patients report difficulty finding medications
• Add it to your patient education materials about magnesium supplementation

Step 2: Write Flexible Prescriptions

When prescribing Magnesium Chloride, consider wording that gives the pharmacist dispensing flexibility:

• "Magnesium Chloride delayed-release tablets" rather than specifying a brand
• "Magnesium Chloride or therapeutically equivalent magnesium salt per pharmacist judgment"
• Include a note: "Substitution permitted" to allow generic or alternative formulation dispensing

This is especially important during shortage periods when a specific product may not be available.

Step 3: Educate Patients About OTC Availability

Many patients don't realize that oral Magnesium Chloride is available without a prescription. Take 30 seconds to inform patients that:

• They can purchase Magnesium Chloride tablets at any pharmacy or online without waiting for a prescription to be processed
• Generic products are therapeutically equivalent to brand-name Slow-Mag
• Typical cost is $8-$15 for a 60-count bottle of generic tablets
• They should look for "Magnesium Chloride" specifically on the label, not other magnesium forms, unless you've approved a substitution

Step 4: Have a Substitution Plan Ready

Maintain a quick-reference substitution guide for when Magnesium Chloride is unavailable:

• Magnesium Citrate — Comparable bioavailability, widely available. Good general substitute. $8-$20/bottle.
• Magnesium Glycinate — Excellent bioavailability, fewer GI side effects. $12-$30/bottle. Best for patients with GI sensitivity.
• Magnesium Oxide (Mag-Ox 400) — Lowest cost option ($5-$12/bottle), but lower bioavailability (~4% vs ~30% for chloride). May need higher doses.
• Magnesium Sulfate injection — Primary substitute for injectable Magnesium Chloride in clinical settings. Adjust dose for elemental magnesium equivalency.

For a detailed comparison, share this patient-facing resource: Alternatives to Magnesium Chloride.

Step 5: Recommend Independent and Compounding Pharmacies

When chain pharmacies are out of stock, independent pharmacies are often the best option because they:

• Source from multiple wholesale distributors
• Can special-order products more nimbly
• May have relationships with compounding suppliers

Compounding pharmacies can also prepare custom Magnesium Chloride formulations when commercial products aren't available. If you write a compounding prescription, specify the desired dose of elemental magnesium and the preferred dosage form.

Alternatives to Discuss with Patients

When Magnesium Chloride isn't available and a patient needs to switch, here's a concise comparison to share:

• Magnesium Citrate: Well-absorbed, widely available. Mild laxative effect at higher doses. Best all-around alternative.
• Magnesium Glycinate: Excellent absorption, gentle on the stomach. Popular for sleep and anxiety support. Slightly more expensive.
• Magnesium Oxide: Budget-friendly but poorly absorbed. Best for patients who primarily need laxative effects or can take higher doses.
• Magnesium Sulfate (IV/IM): Hospital substitute for injectable Magnesium Chloride. Standard of care for emergent hypomagnesemia and eclampsia.

Workflow Tips for Your Practice

Integrating shortage management into your workflow reduces patient callbacks and frustration:

• Proactive communication: When you know a medication is in shortage, mention it at the time of prescribing so patients aren't blindsided at the pharmacy.
• Template documentation: Create an EHR smart phrase for magnesium supplementation that includes alternative options and the Medfinder link.
• Staff education: Brief your medical assistants and front desk staff on common shortage questions so they can provide basic guidance before escalating to you.
• Follow-up labs: When switching magnesium forms, consider ordering a follow-up serum magnesium level in 4-6 weeks to confirm therapeutic adequacy.
• Batch refill management: For patients on chronic magnesium supplementation, recommend they refill with a 7-10 day supply buffer to avoid gaps.

Final Thoughts

The Magnesium Chloride shortage requires proactive provider engagement, but the clinical impact can be minimized with flexible prescribing, patient education, and awareness of alternative magnesium formulations. By directing patients to tools like Medfinder and maintaining a substitution plan, you can ensure continuity of care even during supply disruptions.

For the broader clinical picture, see our companion article: Magnesium Chloride shortage: What providers and prescribers need to know in 2026. And for a cost-saving resource to share with patients, see: How to help patients save money on Magnesium Chloride.