Factors influencing the actions of a poison in the body
1. Quantity: A high dose of poison acts quickly and often resulting in fatal
consequences. A moderate dose causes acute poisoning. A low dose may
have sub-clinical effects and causes chronic poisoning on repeated
exposure. Very large dose of Arsenic may produce death by shock without
dose irritant symptoms, While smaller dose than lethal dose produces its
therapeutic effects.
2. Physical form: Gaseous or volatile poisons are very quickly absorbed and are thus most rapidly effective. Liquid poisons are more rapid than solid poisons. Some poisonous vegetable seeds may pass through the intestinal canal ineffective when taken intact due to their impermeable pericarp. But when taken crushed, they may be rapidly fatal.
3. Chemical form: Chemically pure arsenic and mercury are not poisonous because these are insoluble and are not absorbed. But white arsenic(arsenic oxide) and mercuric chloride are deadly poisonous. Barium sulphide is deadly toxic but barium sulphate is non-toxic.
4. Concentration (or dilution): concentrated form of poison are absorbed more rapidly and are also more fatal but there are some exceptions too.
5. Condition of the stomach: food content presence of food-stuff acts as diluent of the poison and hence protects the stomach wall. Dilution also delays absorption of poison. Empty stomach absorbs poison most rapidly. In cases of achlorohydria, KCN and NaCN is ineffective due to lack of hydrochloric acid, which is required foe the conversion of KCN and NaCN to HCN before absorption.
6. Route of administration: absorption rate is different for different routes.
7. Age: some poisons are better tolerated in some age groups. Opium and its alkaloids are tolerated better by elderly subjects but badly by children and infants. Belladonna group of drugs are better tolerated by children than by adults.
8. State of body health: A well built person with good health can tolerate the action of poison better than a weak person.
9. Presence of disease: In certain diseased conditions some drugs are tolerated exceptionally well e.g.: sedatives and tranquilizers are tolerated in very high dose by manic and deliriant patients.
10. Intoxication arid poisoning states - In certain poisoning cases some drugs are well tolerated, like, in case of strychnine poisoning, barbiturates and sedatives are better tolerated. Whereas in case of barbiturate poisoning any sedative or tranquilizer will accentuate the process of death.
11. Sleep - Due to slow metabolic process and depression of other body functions during sleep, usually the absorption and action of the poison is also slow. But depressant drugs may cause, more harm during the state of sleep.
12. Exercise - Action of alcohol on C.N.S. is slowed during exercise because more blood is drawn to the muscles during exercise.
13. Cumulative action of poisons: Preparations of cumulative poisons (poisons which are not readily excreted from the body and are retained in different organs of the body for a long time) like lead may not cause any toxic effect when enters the body in low dose. But when such poisons enter over a long period of time, may cause harm when their concentration in different tissue reaches high level due to their cumulative property.
14. Tolerance may develop by individuals on long term exposue to a particular poison.
15. Idiosyncracy: some persons may react adversely to a particular drug though the general population tolerates the drug well.
2. Physical form: Gaseous or volatile poisons are very quickly absorbed and are thus most rapidly effective. Liquid poisons are more rapid than solid poisons. Some poisonous vegetable seeds may pass through the intestinal canal ineffective when taken intact due to their impermeable pericarp. But when taken crushed, they may be rapidly fatal.
3. Chemical form: Chemically pure arsenic and mercury are not poisonous because these are insoluble and are not absorbed. But white arsenic(arsenic oxide) and mercuric chloride are deadly poisonous. Barium sulphide is deadly toxic but barium sulphate is non-toxic.
4. Concentration (or dilution): concentrated form of poison are absorbed more rapidly and are also more fatal but there are some exceptions too.
5. Condition of the stomach: food content presence of food-stuff acts as diluent of the poison and hence protects the stomach wall. Dilution also delays absorption of poison. Empty stomach absorbs poison most rapidly. In cases of achlorohydria, KCN and NaCN is ineffective due to lack of hydrochloric acid, which is required foe the conversion of KCN and NaCN to HCN before absorption.
6. Route of administration: absorption rate is different for different routes.
7. Age: some poisons are better tolerated in some age groups. Opium and its alkaloids are tolerated better by elderly subjects but badly by children and infants. Belladonna group of drugs are better tolerated by children than by adults.
8. State of body health: A well built person with good health can tolerate the action of poison better than a weak person.
9. Presence of disease: In certain diseased conditions some drugs are tolerated exceptionally well e.g.: sedatives and tranquilizers are tolerated in very high dose by manic and deliriant patients.
10. Intoxication arid poisoning states - In certain poisoning cases some drugs are well tolerated, like, in case of strychnine poisoning, barbiturates and sedatives are better tolerated. Whereas in case of barbiturate poisoning any sedative or tranquilizer will accentuate the process of death.
11. Sleep - Due to slow metabolic process and depression of other body functions during sleep, usually the absorption and action of the poison is also slow. But depressant drugs may cause, more harm during the state of sleep.
12. Exercise - Action of alcohol on C.N.S. is slowed during exercise because more blood is drawn to the muscles during exercise.
13. Cumulative action of poisons: Preparations of cumulative poisons (poisons which are not readily excreted from the body and are retained in different organs of the body for a long time) like lead may not cause any toxic effect when enters the body in low dose. But when such poisons enter over a long period of time, may cause harm when their concentration in different tissue reaches high level due to their cumulative property.
14. Tolerance may develop by individuals on long term exposue to a particular poison.
15. Idiosyncracy: some persons may react adversely to a particular drug though the general population tolerates the drug well.
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