Overview
Familial primary hypomagnesemia with normocalciuria and normocalcemia — sometimes called isolated familial hypomagnesemia — is a rare inherited condition where the body cannot properly absorb or hold onto magnesium. Magnesium is a mineral your body needs for muscles, nerves, and the heart to work correctly. In this condition, the kidneys lose too much magnesium, causing blood magnesium levels to drop dangerously low. Unlike some related conditions, calcium levels in the blood and urine remain normal, which is an important clue for doctors making the diagnosis. People with this condition often experience muscle cramps, tremors, and in severe cases, seizures — all caused by low magnesium. Symptoms can appear in infancy or early childhood, though the timing varies. The condition is considered 'obsolete' as a separate Orphanet category because it has been reclassified and merged with more precisely defined subtypes of hypomagnesemia as genetic understanding has improved. Treatment focuses on replacing magnesium through oral supplements, sometimes in high doses, taken daily for life. While there is no cure, consistent magnesium supplementation can control symptoms effectively in many patients. Regular blood tests are needed to monitor magnesium levels and adjust dosing over time.
Key symptoms:
Muscle cramps or spasmsTremors or shakingSeizuresMuscle weaknessTingling or numbness in the hands and feetFatigue and low energyIrregular heartbeat or palpitationsIrritability or mood changesDifficulty concentratingNausea or poor appetite
Autosomal dominant
Passed on from just one parent; each child has about a 50% chance of inheriting it
Variable
Can begin at different ages, from infancy through adulthood
Treatments
No FDA-approved treatments are currently listed for OBSOLETE: Familial primary hypomagnesemia with normocalciuria and normocalcemia.
View clinical trials →Clinical Trials
View all trials with filters →No actively recruiting trials found for OBSOLETE: Familial primary hypomagnesemia with normocalciuria and normocalcemia at this time.
New trials open frequently. Follow this disease to get notified.
Specialists
View all specialists →No specialists are currently listed for OBSOLETE: Familial primary hypomagnesemia with normocalciuria and normocalcemia.
Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to OBSOLETE: Familial primary hypomagnesemia with normocalciuria and normocalcemia.
Community
No community posts yet. Be the first to share your experience with OBSOLETE: Familial primary hypomagnesemia with normocalciuria and normocalcemia.
Start the conversation →Latest news about OBSOLETE: Familial primary hypomagnesemia with normocalciuria and normocalcemia
No recent news articles for OBSOLETE: Familial primary hypomagnesemia with normocalciuria and normocalcemia.
Follow this condition to be notified when news becomes available.
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.Which form and dose of magnesium supplement is best for my situation?,How often do I need blood tests to check my magnesium levels?,What should I do if I miss a dose or cannot keep supplements down due to stomach upset?,Should other family members be tested for this condition?,What are the warning signs that my magnesium is getting dangerously low?,Are there any foods or medications I should avoid that could make magnesium levels drop faster?,What is the emergency plan if I have a seizure related to low magnesium?
Common questions about OBSOLETE: Familial primary hypomagnesemia with normocalciuria and normocalcemia
What is OBSOLETE: Familial primary hypomagnesemia with normocalciuria and normocalcemia?
Familial primary hypomagnesemia with normocalciuria and normocalcemia — sometimes called isolated familial hypomagnesemia — is a rare inherited condition where the body cannot properly absorb or hold onto magnesium. Magnesium is a mineral your body needs for muscles, nerves, and the heart to work correctly. In this condition, the kidneys lose too much magnesium, causing blood magnesium levels to drop dangerously low. Unlike some related conditions, calcium levels in the blood and urine remain normal, which is an important clue for doctors making the diagnosis. People with this condition often
How is OBSOLETE: Familial primary hypomagnesemia with normocalciuria and normocalcemia inherited?
OBSOLETE: Familial primary hypomagnesemia with normocalciuria and normocalcemia follows a autosomal dominant inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.