Q. I am a 49-year-old woman. I wake up almost every other hour to drink water throughout the night.
My mouth would be completely dry, like a piece of paper.
I sleep in an air-conditioned room, with the fan on, but will place a glass of water in the room to "moderate" the dryness of the air.
This has been happening for the past year. Is there a reason why I constantly feel thirsty during sleep?
A. It sounds like you are suffering from xerostomia, also known as dry mouth syndrome.
This is characterised by dryness in the mouth, which may be associated with a change in the composition of saliva or reduced salivary flow. In some cases, it may not have an identifiable cause.
It is often seen as a side effect of many types of medication (such as those for high blood pressure) and is more common in elderly people and those who frequently breathe through their mouths.
Dehydration, radiotherapy involving the salivary glands and several diseases can also cause changes in saliva consistency.
Weak kidneys and liver heat
In traditional Chinese medicine (TCM), this problem is likely due to deficiencies in the kidneys, liver and spleen; insufficient qi (vital energy) and yin (the element that cools organs) and blood stasis.
In TCM, the kidneys play an essential role in the distribution, regulation and metabolism of water.
In fact, the foundation of yin fluid that nourishes and moistens the whole body is kidney yin.
When the kidneys are weak, the person can experience dry mouth, teeth, eyes, throat and skin. He would be inclined to drink water, while his palms, feet and chest may feel hot. He may also feel dizzy and experience pains and aches at the lower back and knees.
Genetic disposition, ageing, a weak constitution or chronic illness can impair the kidneys.
As for the liver, it is responsible for the smooth flow of qi in the body.
But ageing and negative emotions, such as fear, stress and anxiety, can weaken the organ.
As a result, the liver qi stagnates and liver heat and fire is created.
This liver heat and fire can dry out the body's yin and create blood stasis. This, in turn, triggers dry mouth, eyes and throat.
Those affected would also be averse to drinking water. They will have painful and swollen joints, a dark complexion, unusually red lips and, for women, irregular menses.
Distribution of water
Distribution of water
Meanwhile, the spleen is linked to the mouth. The organ's primary function is to transform and transport nutrients and water to nourish and moisten the body.
When the spleen's function grows weak - due to ageing, keeping late nights, eating too much spicy food and physical overexertion - it will fail to distribute water to the mouth. This leads to dry mouth with little saliva.
This may be accompanied by bad breath, fatigue, a poor appetite, water retention and diarrhoea.
In addition, a weakened spleen will also be unable to convert nutrients into qi and yin.
Insufficient qi and yin creates internal heat which leads to dry mouth, eyes and throat, along with a hoarse voice, fatigue, sweating and constipation.
Relieving a dry mouth
Chinese herbal medicine, acupuncture and cupping therapy (using fire and cups to create a vacuum on the skin to enhance qi and blood circulation) can help to improve your condition by strengthening your organs.
Herbs such as rehmannia root, common yam rhizome, figwort root, dwarf lilyturf tuber, amur cork-tree, lily bulb and tree peony bark can strengthen the liver and kidneys.
To boost the liver and enhance blood circulation, try Chinese angelica, barbary wolfberry fruit, palmleaf raspberry fruit, safflower and hairyvein agrimonia herb.
Spleen health can be improved with the milkvetch root, medicinal changium root, liquorice root processed with honey, cassia twig and red peony root.
Lastly, herbs that increase qi and yin levels include heterophylly falsestarwort root, common anemarrhena rhizome, dendrobium and Chinese magnolia vine fruit.
To further alleviate the condition, rinse your mouth often with water.
Sip water frequently throughout the day to moisten your mouth, and stay away from alcohol, caffeinated drinks, smoking and foods that are spicy, sweet or salty.
Take regular, small meals and eat easily digestible food, such as soup, porridge, fish, fruit and vegetables.
Take sour fruit and high-fibre food in moderation and chew them well before swallowing to stimulate the secretion of the saliva.
Also, breathe through your nose instead of your mouth.
You may also want to add moisture to the air in your bedroom at night with a humidifier, instead of using a glass of water.
MS LIM LAY BENG
Traditional Chinese medicine practitioner at YS Healthcare TCM Clinic at The Adelphi
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