Low Sodium Cancer Symptoms: Causes, Signs & Treatment | Credihealth

When battling with cancer, certain symptoms like muscle weakness, fatigue, and confusion may develop. They may not be just the cancer and its treatment’s side effects but also could be the signs of low sodium levels, called hyponatremia, which occurs when certain types of cancers like brain or lung tumors interrupt the body’s sodium levels and can lead to severe health issues. So, detecting low sodium cancer symptoms early can make a huge difference in managing and preventing complications and improving quality of life.

This article will help you understand what is hyponatremia and why it occurs in cancer, the key symptoms of low sodium in cancer patients, how cancer treatments affect sodium levels, prevention strategies & treatment options. Read on! 

What Is Hyponatremia?

Hyponatremia is a condition marked by low sodium levels in the blood (below 135 mEq/L). This leads to an imbalance of fluid levels in the body. Additionally, when the sodium balance in the blood is very low, excess water enters the cells and makes them swell up. This can become a dangerous situation, particularly in the brain where there’s less space to extend.

In some cases, hyponatremia is linked with some underlying health problems like cancer. Hence, watching over the symptoms associated with it is crucial for proper diagnosis and treatment. If left untreated, it can be life-threatening. 

Potential Low Sodium Cancer Symptoms

The severity of hyponatremia symptoms depends on how quickly sodium levels drop:

In mild hyponatremia cases, symptoms may not develop. However, if sodium levels in the blood are too low and lower very quickly, an individual may experience these cancer-associated hyponatremia symptoms:

Mild to Moderate Symptoms:

• Fatigue and weakness: Cancer causes the body to hold on to excessive water which dilutes sodium levels.

• Headaches: Low sodium levels cause water to move to brain cells which leads to swelling, thus causing headaches.

• Nausea and vomiting: By retaining excessive water, the body dilutes sodium levels which cause nausea and vomiting.

• Confusion: Research states that cancers like small cell lung cancer (SCLC) can lead to SIADH (Syndrome of Inappropriate Antidiuretic Hormone Secretion), where they produce ADH in excessive amounts. This causes the kidney to retain water, contributing to low sodium levels with symptoms like confusion. 

• Muscle cramps or spasms: Low sodium balance can interrupt the activity of nerve impulses that trigger contractions and cause muscle cramps or spasms.

• Loss of appetite: Low sodium levels due to cancer can impact the brain and other organs, leading to weakness, fatigue, and confusion which contribute to loss of appetite. Sometimes, cancer can directly impact appetite.

Severe Symptoms (If Sodium Levels Lower Significantly):

• Severe confusion or delirium: SIADH due to cancer or some cancer treatments like chemotherapy can lead to severe confusion or sudden changes in mental state like hallucinations.

• Seizures: Due to SIADH, the body holds on excess water which dilutes the sodium levels, leading to swelling up of the brain and potentially seizures.

• Coma (in extreme cases): When sodium levels drop too much and fast, it can cause brain dysfunction and swelling as the brain is highly sensitive to sodium imbalance. This contributes to coma.

• Decreased consciousness: Swelling up of brain cells due to low sodium levels can lead to neurological symptoms like decreased consciousness.

Why Do Cancer Patients Develop Low Sodium Levels?

Cancer and its treatments can disrupt sodium balance in several ways:

• SIADH (Syndrome of Inappropriate Antidiuretic Hormone Secretion): Cancer-induced hyponatremia can be caused by SIADH (frequently develops in small-cell lung cancer) which triggers too much release of ADH (Antidiuretic Hormone), retaining water and diluting sodium levels.

• Cancer Treatments: Radiation therapy, chemotherapy, and other cancer treatments can impact kidney function or increase fluid retention, interrupting sodium balance.

• Tumor-Related Effects: Certain tumors may interfere with the normal balance and stability of the hormone in the body, leading to sodium imbalance.

• Gastrointestinal Problems: Diarrhea, malabsorption, or vomiting due to cancer or its treatment can also contribute to excess sodium loss.

• Kidney or liver Dysfunction: Cancers impacting the kidneys or liver can lead to an overload of fluid which causes low sodium levels.

• Excessive Fluid Intake: Cancer patients might consume plenty of water because of medication side effects or dry mouth which can further lead to diluted sodium levels.

Complications of Untreated Hyponatremia

Hyponatremia or low sodium levels that develop gradually or decrease mildly are not likely to pose any complications if treated on time. However, in sudden drop in sodium levels (in less than 48 hours) or in case of too low sodium levels, there is the risk of severe issues if left untreated. Those complications include:

How Is Hyponatremia Treated in Cancer Patients?

Doctors treat low sodium levels based on severity:

• Fluid Restriction: Limit intake of fluids like water, coffee, tea, or soup to alleviate the risk of further dilution of sodium levels.

• IV Sodium Solutions: Intravenous saline or hypertonic saline in severe cases may be provided to slowly restore lost sodium levels.

• Medications: Vaptans (e.g. Tolvaptan, Demeclocycline, or Conivaptan): Blocks excessive ADH release and restores sodium levels and Diuretics Removes too much water while maintaining the balance of sodium in the body.

• Treating Underlying Causes: Address specific conditions like cancer, SIADH, or kidney dysfunction that are causing low sodium levels.

• Adjusting Cancer Treatment: If chemotherapy or other cancer medications are causing low sodium levels in the blood, doctors may adjust the treatment plan.

• Hospitalization: In severe cases where symptoms such as coma, seizures, or confusion occur, doctors may ask for immediate hospitalization for close monitoring. 

When to Seek Medical Help?

See a healthcare provider immediately, if you or your loved ones with cancer experience these symptoms of low sodium levels:

• Severe confusion

• Severe fatigue

• Seizures

Doctors can help with blood tests to determine sodium levels and provide correct treatment. 

Tips to Prevent Low Sodium Levels in Cancer Patients

Follow these tips to prevent the lowering of sodium levels in the blood:

• Drink water (but not excessively): Drink water in moderate amounts as excessive hydration can worsen hyponatremia.

• Monitor your medications: Certain cancer medications can lead to sodium imbalances, causing some side effects. So speak with your doctor about them.

• Monitor electrolytes regularly: Go for frequent blood tests to keep track of your sodium levels and modify the treatment as required.

• Change your diet: Increase your sodium (salt) intake by consuming sodium-rich foods (under a doctor’s supervision) to regulate your sodium levels.

• Treat associated conditions: Get the proper treatment for conditions that contribute to low sodium levels, for instance, certain cancers and their treatment or SIADH.

• Watch for the symptoms: If you have medical issues like cancer that can raise the possibility of low sodium levels, be aware of the symptoms of low blood sodium. 

Does Balancing Sodium Levels Improve Cancer Survival?

Yes! A study found that early sodium correction in small-cell lung cancer (SCLC) patients significantly improves treatment outcomes and survival rates. By maintaining a stable sodium balance, cancer patients can experience:

• Better treatment response

• Improved cognitive function

• Reduced hospitalization risk

Final Thoughts

Recognizing the low sodium cancer symptoms; from nausea, vomiting, fatigue, weakness, and muscle cramps to severe confusion, seizures, and coma is important for early diagnosis and treatment. 

Regular sodium monitoring, proper hydration, and timely medical intervention can prevent complications and improve patient outcomes. If you or a loved one is undergoing cancer treatment, speak to your doctor about monitoring sodium levels to ensure a safer and more effective recovery journey.

If a cancer patient experiences severe confusion, seizures, or unconsciousness, seeking urgent medical care is essential.

If you want to learn more consult your healthcare provider or check out reputable sources like American Cancer Society for further insights.

Read Also: What Causes Low Sodium Levels In The Elderly

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