What is Magnesium Toxicity?
Magnesium is a mineral that our body naturally contains and that we also get from the food we eat every day. This mineral is vital for various body functions such as building proteins, forming bones, controlling blood pressure, ensuring the nerves work properly, and conducting electricity in the heart. However, having too much magnesium, whether from eating too much or the body not getting rid of enough, can lead to serious health problems.
This topic discusses the reasons and early signs of having too much magnesium in the body. It also emphasizes the need to identify and treat high magnesium levels as soon as possible. Effective teamwork among healthcare professionals is key in preventing life-threatening complications.
What Causes Magnesium Toxicity?
Magnesium toxicity, also known as an overdose of magnesium, is uncommon in most people. However, certain individuals have an increased risk of developing this condition. Magnesium is usually removed from our bodies by our kidneys, so people with long-term kidney diseases are particularly vulnerable. Especially, those who have a low creatinine clearance (a measure of how well the kidneys filter wastes from the blood) of less than 30 ml per minute have a higher risk.
People who depend on dialysis (a treatment to filter and clean the blood when kidneys are not able to do this job) can also see a rapid increase in their magnesium levels if they miss their treatments. Apart from this, people undergoing treatment for cancer might also be at risk. This is because their cells, which have a higher concentration of magnesium than their blood plasma, can break down at high rates (a process known as hemolysis), releasing this extra magnesium into the bloodstream.
Also, some women being treated for a condition called preeclampsia (a pregnancy complication characterized by high blood pressure) may be at risk. This is because the high dosage of magnesium used to prevent seizures in preeclampsia treatment can result in magnesium toxicity.
Recognizing the causes of magnesium toxicity, whether due to the body absorbing too much magnesium or not expelling enough of it, is crucial for identifying individuals at risk. This insight can help prevent future instances of magnesium toxicity.
Risk Factors and Frequency for Magnesium Toxicity
Magnesium toxicity can affect anyone, and it often occurs due to an underlying health issue or from taking too much magnesium. Women, in particular, are more prone to magnesium toxicity. This is because magnesium is commonly used to treat pre-eclampsia, a condition that affects about 3% of pregnant women. The issue of magnesium toxicity is higher in the U.S. compared to the rest of the world, probably due to the easy access to supplements that contain magnesium. In fact, about 9.3% of hospital patients in the U.S. have been found to have too much magnesium in their bodies.
Signs and Symptoms of Magnesium Toxicity
Magnesium toxicity isn’t detected through routine checks and usually presents with symptoms that could indicate other health problems. This means it’s crucial to get a comprehensive patient history to identify its cause. The causes could include issues with the kidneys, taking too much of certain medications like antacids and laxatives, or having received chemotherapy recently. People on dialysis who may have missed appointments are particularly at risk of magnesium toxicity. Symptoms can vary widely and include changes in vision, blushing, muscle paralysis, and excessive sleepiness. Still, a patient losing their knee-jerk reflex could be a major clue of this condition. Furthermore, if a patient’s receiving a continuous magnesium infusion – common with conditions like preeclampsia – their knee-jerk reflex needs to be monitored regularly.
- Impaired kidney function
- Overusing medications like antacids and laxatives
- Recent chemotherapy
- Missed dialysis treatments
- Changes in vision
- Blushing
- Muscle paralysis
- Excessive sleepiness
- Loss of knee-jerk reflex
Testing for Magnesium Toxicity
If your doctor suspects that your magnesium levels might be too high, they might order a simple blood test. This test measures the amount of magnesium in your blood. If this test shows that your magnesium concentration is higher than 2.2 mEq/L or 1.1 mmol/L, this would mean that there is too much magnesium in your blood, a condition also known as hypermagnesemia.
In addition to the blood test, your doctor may want to do an ECG, or electrocardiogram. This is an easy test that can show if there are dangerous irregular heartbeats that could require urgent treatment. High magnesium levels is one thing that might cause irregular heartbeats.
Your doctor may also order another kind of blood test, also known as a complete metabolic panel. A complete metabolic panel checks for anything unusual in the blood, not just magnesium. This test includes checks on phosphorus levels and how well your kidneys are working because your kidneys play an important role in removing magnesium from your body.
Treatment Options for Magnesium Toxicity
If you have too much magnesium in your body, the first step in treating this condition is to stop taking all supplements and medications that contain magnesium. If the situation is severe, a medication known as calcium gluconate can be given intravenously (through a vein) to counteract the effects of the magnesium. But to fully treat this condition, it’s necessary to decrease the amount of magnesium in your body.
If your kidneys are working normally, this can be achieved by receiving intravenous diuretics – medications that help your kidneys remove extra fluids and magnesium. But if your kidneys are not working well, dialysis treatment is needed. Dialysis is a procedure that acts as an artificial kidney, removing waste and extra fluids (including magnesium) from your blood when your kidneys can’t perform this function.
What else can Magnesium Toxicity be?
Magnesium toxicity can be hard to identify because its symptoms can be quite vague. When trying to diagnose it, doctors should also make sure to consider other health issues that could cause an imbalance in your body’s electrolytes. For this reason, a proper medical evaluation should include checks for levels of several important substances in the body like potassium, calcium, phosphorus, and magnesium.
- Lithium
- Depression
- Hypothyroidism
- Addison’s disease
- Familial hypocalciuric hypercalcemia (a rare genetic disorder)
- Milk alkali syndrome
What to expect with Magnesium Toxicity
If detected and treated promptly, magnesium toxicity can be completely resolved without long-term impacts. This means that if it is treated quickly, it won’t affect your quality of life, cause any lasting complications, or reduce your lifespan. The treatment generally involves using calcium gluconate to stabilize the high magnesium levels, and diuretics or dialysis to reduce it.
However, if magnesium toxicity is not treated, it can become very serious and lead to a high risk of death due to respiratory paralysis (where your breathing muscles stop working) and cardiac arrest (unexpected heart attack). This is why it’s important to treat it early.
Possible Complications When Diagnosed with Magnesium Toxicity
When there is too much magnesium in the blood (a condition known as hypermagnesemia), it can affect the whole body and specific organs depending on how high the levels of magnesium are. Early signs include feeling hot or flushed, feeling sick or throwing up, and general muscle weakness. As the levels of magnesium get higher, the muscle weakness can become so severe that people lose their deep tendon reflexes, and even become completely paralyzed, which can potentially compromise their ability to breathe. Further complications can occur in the cardiovascular system and can start with low blood pressure and a slow heart rate. If the high levels of magnesium aren’t treated, this could eventually lead to a complete block of the heart, and even a heart failure.
Common Side Effects:
- Feeling hot or flushed
- Feeling sick or throwing up
- General muscle weakness
- Loss of deep tendon reflexes
- Extreme cases of muscle weakness could lead to complete paralysis
- This paralysis could cause breathing problems
- Low blood pressure
- Slow heart rate
- In untreated cases, it could block the heart completely and even cause a heart failure
Preventing Magnesium Toxicity
It’s crucial for patients to understand the effects of having a high magnesium level in the body as this knowledge can help in preventing magnesium toxicity. Magnesium is an electrolyte, which helps control how your muscles and nerves work, and balance blood sugar levels. It is not as well-known as other electrolytes like potassium, sodium, and calcium, but it’s just as important to remember. This is particularly crucial for people with chronic kidney disease, those being treated for preeclampsia (a pregnancy condition associated with high blood pressure), and individuals on dialysis (a treatment to remove wastes and excess water from the blood, typically used for people with failed kidneys).
