Posology is one of the most important and practical branches of Homoeopathic science. Selecting the correct remedy is only half the work of a physician; the other half lies in selecting the correct potency, quantity, form, and repetition of that remedy. Without proper posology, even the most accurately selected similimum may fail to act.
This article presents a complete discussion of Posology and Homoeopathic Posology—its meaning, principles, evolution, types of doses, repetition, and the philosophy behind single remedy prescription.
POSOLOGY
Etymology
The term posology originates from the Greek words:
- “Posos” meaning how much
- “Logos” meaning study or discourse
Thus, posology literally means the study of “how much” medicine should be given.
Definition of Posology
Posology means the doctrine of doses of medicine.
The term dose is derived from the word “dosis”, meaning the quantity of a drug or therapeutic agent to be taken at one time or in divided amounts within a stated period.
Definition of Homoeopathic Posology
In Homoeopathy, a dose includes:
- The particular preparation of medicine used
- The potency
- The quantity and form
- The number of repetitions
Thus, homoeopathic posology is the study of the doctrine of these doses.
Difference Between Homoeopathic and Allopathic Concept of Doses
Allopathic Concept
In allopathy, dose refers to the material quantity of medicine—measured in drops, grains, or milligrams—sufficient to produce physiological effect without endangering life.
It focuses purely on material quantity.
Homoeopathic Concept
In Homoeopathy, the concept of dose is broader:
- It refers to the preparation (Mother tincture, 6C, 30C, etc.)
- It refers to the quantity and form (drop, globule, powder, liquid dilution)
- It refers to the repetition
Example:
“Opium 30” may be given:
- As a single dose
- Repeated every 4 hours
- Given weekly
- In liquid form or globules
Thus, Homoeopathy views dose dynamically—not materially.
Selection of Potency
Even a correctly selected remedy will fail if given in an improper potency.
Potencies are broadly divided into:
- Low potency – Below 30
- Medium potency – 30, 200, 1M
- High potency – Above 1M
According to Voisin:
- Low potencies → Act on organs
- Medium potencies → Influence function
- High potencies → Act on psyche
Factors Responsible for Selection of Potency
1. Susceptibility of the Patient
This is the most important factor.
General Rule:
Greater susceptibility → Higher potency → Smaller quantity.
(a) Age
- Children → High susceptibility → Medium or high potency
- Old age → Reduced susceptibility
- Dead person → Nil susceptibility
(b) Constitution and Temperament (Dr. Stuart Close)
Higher Potencies Suitable For:
- Nervous, sanguine, choleric temperament
- Intelligent, sensitive individuals
- Quick reactors
Lower Potencies Suitable For:
- Phlegmatic individuals
- Coarse, sluggish constitution
- Muscular, gross habits
(c) Van Grauvogl’s Constitution
- Hydrogenoid → Lower potency (3X–6X)
- Oxygenoid → 20X–30X
- Carbonitrogenoid → High potencies (30C and above)
(d) Habit and Environment
Higher Potencies:
- Intellectual workers
- Sedentary lifestyle
- Emotional, imaginative people
Lower Potencies:
- Labourers
- Tobacco workers
- Druggists
- Chemical workers
(e) Pathological Condition
In advanced organic pathology:
- Vital reaction is low
- Material doses may be required
Example:
Chronic valvular heart disease → Crataegus 10–15 drops
2. Nature of Disease
Acute Diseases
- High susceptibility
- High potency
- Frequent repetition
Chronic Disease (Without Organic Change)
- Start with 200C (generally safe rule)
Chronic Disease (With Organic Change)
- Lower potency
Mental Disease
- Higher potency
Approximate Dose in Homoeopathic Pharmacy
| Form | Adult | Child | Infant |
|---|---|---|---|
| Globules | 4 | 2 | 1 |
| Tablets | 2 | 1 | ½ |
| Tincture | 1 drop | 1 drop | 1 drop |
Various Kinds of Doses
1. Maximum Dose
Largest possible amount not harmful to life.
2. Lethal Dose
Amount capable of causing death.
3. Booster Dose
Subsequent dose to enhance initial effect.
4. Fractional Dose
Divided dose at short intervals.
5. Physiological Dose
Stimulates normal physiology.
6. Minimum Dose
Defined in Aphorisms 246 and 280 of the Organon as:
That smallest dose sufficient to overpower and annihilate disease while producing only slight aggravation.
Evolution of Minimum Dose
- 1786 → Large doses used
- 1796–1797 → Several grains prescribed
- 1801 → First indication of infinitesimal dose
- 1813 → Concept of minimum dose established
To avoid violent aggravation, Hahnemann reduced the dose gradually and formulated the principle of minimum dose.
Advantages of Minimum Dose
- Prevents violent aggravation
- Avoids medicinal disease
- Prevents drug addiction
- Ensures gentle cure
- Verified by Arndt-Schultz law
- Small dose stimulates
- Medium dose paralyses
- Large dose kills
Repetition of Dose
As Per 5th Edition of Organon
Do Not Repeat When:
- Improvement is continuous
Repeat When:
- Improvement stops
- Original symptoms return
Acute Diseases
Repeat every:
- 24, 12, 8, 4 hours
- In severe cases: Every hour or 5 minutes
Chronic Diseases
Repeat:
- Every 7–14 days
Higher potency → Less repetition
Lower potency → More frequent repetition
Kent’s Rules of Repetition
Repeat when:
- Improvement stands still
- Original symptoms return in same pattern
Wait if:
- Improvement continues
Single Remedy Principle
Homoeopathy insists on single, simple medicinal substance because:
- Disease totality is single
- Vital force is single
- Remedies were proved singly
- Polypharmacy creates confusion
- It obscures second prescription
As stated in Organon:
- Complex means are unnecessary when simple means suffice
- One simple remedy is sufficient
Posology is not merely about how much medicine to give; it is the art and science of selecting:
- The correct potency
- The correct quantity
- The correct form
- The correct repetition
Homoeopathic posology is dynamic, individualized, and guided by susceptibility, disease nature, pathology, and constitutional factors.
The success of Homoeopathic treatment depends not only on the similimum but equally on the judicious application of the minimum dose and proper repetition.
A true Homoeopathic physician masters both remedy selection and posology—only then can cure be rapid, gentle, and permanent.