Modern Pharmacognocy drug drug and drug food interaction

1. MODERN
PHARMACOGNOSY-I
• BIO DRUG-DRUG AND BIO DRUG-FOOD
INTERACTION
SATHYAMOORTHY. K
M.PHARM 1YEAR 1 SEMESTER
JKKMRF COLLEGE OF PHARMACY
KOMARAPALAYAM

2. CONTENT
• Introduction
• Types of drug interaction
• Effect of drug interaction
• Factors contributing to drug interaction
• Mechanism
• Pharmaceutical interactions
• Pharmacokinetic interaction
• Pharmacodynamic interaction
• Consequences of drug interaction
• Reducing the risk of drug interaction
• Influence of smoking and alcohol
• Bio drug –food interaction

3. INTRODUCTION
Drug interaction
Defined as the pharmacological activity of one drug is altered by the concomitant use
of another drug or by the presence of some other substance.
Objective drug
The drug whose activity is effected by such an interaction
Precipitant
The agent which precipitates such an interaction

4. TYPE OF DRUG INTERACTIONS

5. THE NET EFFECT OF DRUG INTERACTION
Generally quantitative
i.e. increased or decreased effect
Seldom qualitative
i.e. rapid or slower effect
Adverse effect
Precipitation of newer or increased adverse effect

6. FACTORS CONTRIBUTING TO DRUG INTERACTION
1. Multiple drug therapy
2. Multiple prescribers
3. Multiple pharmacological effect of drug
4. Multiple disease predisposing illness
5. Poor patient compliance
6. Advancing age of patient
7. Drug –related factors

7. MECHANISMS OF
DRUG INTERACTIONS
The three mechanisms by
which an interaction can
develop are
 Pharmaceutical interactions
 Pharmacokinetic interactions
 Pharmacodynamic
interactions

8. PHARMACEUTICAL
INTERACTIONS
 Also called as incompatibility
 It is a physicochemical interaction that
occurs when drug are mixed in I.v
infusion causing precipitation or
inactivation of active principles.
 Example :Ampicillin, chlorpromazine &
barbiturates interact with dextran in
solutions and are broken down or form
chemical compounds.

9. PHARMACOKINETIC
INTERACTIONS
• These interactions are those in which ADME
properties of the object drug is altered by the
precipitant and hence such interactions are also
called as ADME interactions.
• The resultant effect is
altered plasm concentration of the object drug.
• These are classified as:
• Absorption interactions
• Distribution interactions
• Metabolism interactions
• Excretion interactions

10. MAJOR MECHANISM OF ABSORPTION INTERACTIONS ARE:
1. Complexation and adsorption
2. Alteration in GI pH
3. Alteration in gut motility
4. Inhibition of GI enzymes
5. Alteration of GI micro flora
6. Malabsorption syndrome

11. ABSORPTION INTERACTION

12. DISTRIBUTION INTERACTIONS
Are those where the distribution pattern of the object drug is altered.
The major mechanism for this interaction is alteration in protein-drug binding.

13. METABOLISM INTERACTION

14. EXCRETION INTERACTIONS

15. PHARMACODYNAMIC INTERACTIONS
• Are those in which the activity of the object drug at its site of action is altered by the
precipitant.
• Such interactions may be direct or indirect.
These are of two types
1.Direct pharmacodynamic interaction.
2.Indirect pharmacodynamic interaction.

16. • In which drugs having similar or opposing pharmacological effect are used concurrently.
• The three consequences of direct interactions are:
• 1.Antagonism.
• 2.Addition or summation.
• 3.Synergism or potentiation.
DIRECT PHARMACODYNAMIC INTERACTIONS

17. CONSEQUENCES OF DRUG INTERACTION
The consequences of drug interactions may be:
• Major-life threatening.
• Moderate-deterioration of patient status.
• Minor - little effect.

18. REDUCING THE RISK OF DRUG INTERACTIONS
1. Identify the patients risk factors
2. Take through drug history
3. Be knowledge about the actions of the drugs being used
4. Consider therapeutics alternatives
5. Avoid complex therapeutics regiments when possible
6. Educate the patient
7. Monitor therapy

19. INFLUENCE OF SMOKING ON DRUG INTERACTIONS
Smoking increases the activity of drug metabolizing enzyme in the liver, with the result
that certain therapeutics agents.
Example : Diazepam, propoxyphene, theophylline , olanzapine are metabolized more
rapidly and their effect is decreased.

20. INFLUENCE OF ALCOHOL ON DRUG INTERACTION
Chronic use alcohol beverages may increases the rate of metabolism of drug such as
warfarin and phenytoin, probably by increasing the activity of hepatic enzymes.
• Acute use of alcohol by non alcoholic individuals may cause an inhibition of hepatic
enzyme
• Use of alcohol beverages with sedatives and other depressants drugs could result in
an excessive depressant response.

21. INFLUENCE OF FOOD DRUG INTERACTION
• effects the rate and extent of absorption of drugs from the GI tract.
• Example: Many anti biotics should be given at least 1hr before or 2hr after meals to
achieve Optimal absorption.
• The type of food may be important with regard to the absorption of concurrently
administered Drugs.
• Example: Dietary items such as milk and other dairy products that contain calcium
may decrease the absorption of tetracycline and fluoroquinolone derivatives.
• Diet also may influence urinary pH values.