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CLEARANCE

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CLEARANCE :- Ø   Clearance is the most important parameter in clinical drug applications and is useful in evaluating the mechanism by which a drug is eliminated by the whole organism or by a particular organ. Ø   Clearance is a parameter that relates plasma drug concentration with rate of drug elimination according to following equation:       Clearance = Rate of Elimination             -------15                            Plasma drug concentration                                                   Or Cl = (dx/...
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APPARENT VOLUME OF DISTRIBUTION

APPARENT VOLUME OF DISTRIBUTION:- Ø   Apparent volume of distribution and clearance are two separate and independent pharmacokinetic characteristics of a drug. Since they are closely related with physiologic mechanisms in the body, they are called as primary parameters.         V d =     Amount of drug in the body    =     X ------ 12                        Plasma drug concentration          C Ø   V d is a measure of the extent of distribution of drug and is expressed in litres. The best and simplest way of estimating V d of a drug is administering it by rapid IV injection and using following equation:         V d =    Xo / Co = iv bolus dose / Co  ------13 Ø   Equation 13 can only b...
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ONE COMPARTMENT OPEN MODEL(Instantaneous Distribution Model)

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·          The one compartment open model is the simplest model which depicts the body as a single, kinetically homogeneous unit having no barriers to the movement of drug and final distribution equilibrium between drug in plasma and other body fluid is obtained instantaneously and maintained at all times. ·          This model thus applies only to those drugs that distribute rapidly throughout the body. ·          The anatomical reference compartment is the plasma and concentration of drug in plasma is representative of drug concentration in all body tissues i.e. any change in plasma drug concentration reflects a proportional change in drug concentration throughout the body. ·          The term open indicates that the input (availability) and output (elimination) are unidirectional and that the drug can be eliminated ...
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Pharmacokinetics: Physiological Model

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PHYSIOLOGIC MODEL o    Also called as Blood flow rate –limited models and perfusion rate limited models. o    Physiological models describe the drug disposition in terms of realistic physiological parameters such as blood flow and tissue partition co-efficient. o    The number of compartments to be included in the model depends upon the disposition characteristics of drug. o    Organs such as bone that have no drug penetration are excluded. o    Most physiologic models are based on the assumption that the drug movement within a body region is much more rapid than its rate of delivery to that region by the perfusion blood and, therefore the model is said to be perfusion rate limited. The assumption is however applicable to the highly membrane permeable drugs i.e. low molecular weight, poorly ionized and highly lipophilic drugs. o    For, highly polar, ionized and charged drugs, the model is referred to as membra...
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Introduction of Latin to English, weights and measures in dispensing pharmacy

Definition: It is defined as supply of medicine to individual patients according to the prescription written by registered medical practitioner. General dispensing procedure: o    Give the prescription. o    Check out dose and direction of dispensing. o    Dispense the medicine. o    Take a medicine into a container. o    Fix the label onto the container. o    Supply the container to the patient with conditions associated with medicine. Introduction of latin to english translation Latin Terms and Abbreviations Term or Phrase Abbreviation Meaning Quantum q.s.   As much Sufficiat as is sufficient sufficit  as is sufficient Sufficientem q.s. As ...
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PATIENT RELATED FACTORS AFFECTING ON DRUG ABSORPTION

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Physiologic Factors Related to Drug Absorption:   The systemic absorption of a drug is dependent on   The physicochemical properties of the drug,   The nature of the drug product, and   The anatomy and physiology of the drug absorption site.  1. Membrane Physiology A. Nature of Cell Membrane  The fluid mosaic model, proposed by , explains the transcellular diffusion of polar molecules.   According to this model, the cell membrane consists of globular proteins embedded in a dynamic fluid, lipid bilayer matrix. These proteins provide a pathway for the selective transfer of certain polar molecules and charged ions through the lipid barrier.  As shown in , transmembrane proteins are interdispersed throughout the membrane. Two types of pores of about 10 nm and 50 to 70 nma were inferred to be present in membranes based on capillary membrane transport studies. These small pores provide a channel through which water, ions, and dissol...
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PLANT LAYOUT FOR CAPSULE MANUFACTURING DEPARTMENT & MANUFACTURING PROCESS

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PLANT LAYOUT  FOR CAPSULE MANUFACTURING DEPARTMENT: ENVIRONMENT CONDITION FOR CAPSULE FILLING AREA Humidity:          Not more than 35% RH Temperature:    Not more than 25% Area of each room, position of equipments, washing, drying, and sanitary facilities must be in accordance with GMP. MANUFACTURING PROCESS: CHEMCAPS Limited is an India based young and dynamic organization engaged in the manufacture and export of 'empty hard gelatin capsules' under the brand name of 'Chemlock' for discerning customers around the globe. COMPOSITION                                     Gelatin                                     Water                       ...
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