When determining the safe dosage of a Chinese medicine, the nature of both the medicine and the patient are taken into consideration during prescription. If the dosage is inappropriate, the curative effects of the Chinese medicines will be diminished.
Consider the medicine
If the medicine is of high quality and potency, its dosage must not be too high; if the medicine is light in weight, a low dosage should be given, e.g. dried medicinal flowers and leaves. For medicinal metals, stones, shells or aquatic materials, a high dose is appropriate.
If the medicine is mild in nature and taste, a high dosage is also appropriate.
Consider the patient
- Age: The dosage taken by children and the old should be lower as compared to the dosage taken by a strong, young adult. Children below 5 years of age should consume only a quarter of an adult’s dosage. Children above the age of 5 or 6 will take half of an adult’s dosage.
- Gender: Dosage taken by a male or female is almost similar. During pregnancy and menstruation, potent medicines for removing blood stasis and clearing obstruction in meridians should not be prescribed in too high a dosage.
- Physique: A high dosage may be given to one who has a strong physique, while a weak person who is taking tonifying medicines should begin with a low dose first, increasing the dosage over time.
- Illness: Dosage for treating a newly contracted illness should be high, whereas patients having chronic illness should take a low dose. Patients with a serious or acute disease are given a high dosage, while those with mild or minor illnesses should take a low dosage.
Consider the application
- For use as a single herb, a high dosage is prescribed.
- For use in a prescription as a main herb, use a high dose; if used as an auxiliary herb, use a low dose.
- The dosage will also differ depending on the desired effect. Take betel nut for instance. If used to promote the normal flow ofqi (vital energy), remove stagnation ofqi, or to induce diuresis, 6 to 15g is prescribed; if used to get rid of parasites, a dosage of 60 to 120g is needed. Medicines should be taken as instructed and advised by a Chinese physician.
The ABC method of administration
A: When to consume medicine
-In the early morning, on an empty stomach when the medicine can take full effect. This is a suitable time to take hydrogogue therapeutic medicines for drastic purgation.
-Before meals, on an empty stomach. This time is suitable for taking parasite-expelling medicines , purgative medicines and medicines for treating stomach and intestinal diseases.
-After meals, on a full stomach, the stomach is less prone to irritations. Medicines should be taken one hour after meals. This is a suitable time to take medicines which relieve food retention.
-Before sleep. Medicines take effect more easily at this time. This is therefore a suitable time to take tranquillisers , laxatives , medicines to stop seminal emission, etc.
-Specific time: some medicines need to be taken at a specific time for curative effects. E.g. medicines for preventing malarial attacks should be taken 2 hours before the onset of the attack. Use medicines as advised by the physician.
B: How much medicine to take
For most common illnesses, 1 full dose is prepared daily and consumed in 2 or 3 small portions throughout the day. For serious illnesses, the medicine is taken once every 4 hours throughout the day and night.
For sweat-inducing and purgative medicines, medication should be stopped when the curative effect is achieved. These medicines are not suitable for frequent use. Patients who are vomiting should take repeated small doses.
C: How to take medicine
-Decoction : should be taken warm. Cold syndrome medicines, medicines for relieving exterior syndrome should be taken hot, while heat syndrome medicines can be taken cold.
-Pills : small capsules should be swallowed with warm water while large capsules are broken into smaller portions for swallowing.
-Medicinal powder : taken after blending with honey, or put in capsule to be swallowed.
-Soft herbal extract : taken after mixing with boiled water. These should not be poured directly into the mouth as the stickiness of the medicine can irritate the throat and lead to vomiting.
-Medicinal granules : taken after mixing with boiled water.