Clinical Pharmacology Flashcards
What is a drug?
external substance that acts on living tissue to produce a measurable change in the function of that tissue
Name 4 types of drugs used in Dentistry?
- LA
- Antimicrobials- treat and prevent infections
- anxiolytics - reduce anxiety
- analgesics- reduce postoperative pain
What can drugs do?
- simulate normal body communications
- interrupt normal body communications
- act on non-host organisms to aid body defences
What is host communication? (simple definition)
How your body speaks to itself:
= hormone messages - general information to ALL tissues
= neural messages - targeted information for SPECIFIC tissues
Give 4 examples of hormone systems in the body. (4)
- thyroid hormones ( T3 & T4)
- insulin/glucagon
- cortisol/aldosterone
-sex hormones
How to thyroid hormones work?
they work to balance the body’s metabolism:
- too little - hyperthyroidism
- too much - hypothyroidism
Which drugs can replace the missing active hormone - T3 & T4?
thyroxine dose adjusted to correct level gradually
replacement medicine acts directly in the TISSUES
- no direct effect on thyroid gland
Where do replacement medicines act? (with regards to thyroid hormones)
directly in the tissues, no direct effect on thyroid gland
What are the signs of hypothyroidism? (5)
- cold intolerance
- coarse skin
- memory loss
- slow pulse
- low metabolism
What are the signs of hyperthyroidism? (5)
- rapid metabolism
- high pulse rate
- sweating & heat intolerance
- anxiety and agitation
- weight loss
What are two divisions of the autonomic nervous system?
Sympathetic
parasympathetic
Is adrenaline part of the sympathetic or parasympathetic nervous system?
adrenaline (epinephrine) is part of the sympathetic nervous system. “the fight or flight response”
Is acetylcholine part of the sympathetic or parasympathetic nervous system?
Within the parasympathetic nervous system alone, the postganglionic neuron releases acetylcholine as its primary neurotransmitter. Responsible for the ‘rest and digest phase’
Give a sympathetic and parasympathetic example for the control of heart rate:
= sympathetic- adrenergic stimulation (speeds up the heart via beta- receptors)
= parasympathetic - cholinergic stimulation ( slows the heart via cholinergic receptors)
Give 4 examples of ‘autonomic’ drugs?
= adrenaline (beta agonist)
= atenolol (beta blocker)
= pilocarpine (cholinergic agonist)
= atropine (cholinergic blocker)
Define ‘topical’
drug applied to the tissue where it acts
define systemic
drug applied to the whole organism
define parenteral
drug administered by injection
define transdermal?
drug applied to the skin for absorption
define subcutaneous
drug injected into the tissues of the skin
define intramuscular
drug injected into muscle
define intravenous
drug injected into a vein
define transmucosal
drug applied to the mucosa for adsorption
What can go wrong with drug administeration?
- allergy - mind
- allergy - severe - anaphylaxis
- drug-drug interactions
- acute toxic reactions
How does a drug-drug interaction occur?
One drug interferes with the adsorption, action or metabolism of another
Name 2 protein binding drugs?
=Warfarin: a blood thinner used to prevent blood clots, binds to albumin in the blood.
=Aspirin: a pain reliever and anti-inflammatory drug, binds to both albumin and glycoprotein in the blood.
=Diazepam: a benzodiazepine used to treat anxiety and seizures, binds to albumin in the blood.
=Ibuprofen: a nonsteroidal anti-inflammatory drug (NSAID), binds to albumin in the blood.
Name three drugs you may be hesitant to prescribe if a patient is taking either warfarin or simvastatin?
- erythromycin
- fluconazole
- carbamazepine
Name three examples of acute toxic reactions?
- bone marrow suppression
- hepatotoxicity & biliary stadid
- acute nephrotoxicity
Name two subheading of prescribing errors?
= the decision to prescribe
= prescribing the wrong drug
Why might a clinician question the decision to prescribe?
1 = would a different treatment be a better option
= most common dental prescribing error
2= prescribing the wrong drug
=ADR
= ineffective
=less effective
3= incorrectly completing the prescription
What 8 things should be on a prescription form? (9)
= patient’s name, address, age (under18)
= patients identifier - DoB, CHI number
= number of days treated
= drug to be prescribed
= drug formulation and dosage
= instructions on quantity to be dispensed
= instruction to be given to patient
= signed- identifier to prescriber
What 3 things ensure prescription validity?
= six months from date issues
= more than one item on a script
= more than one repeated dispensing occasion (useful when patient is getting a medication over several months0
What are the advantages of written instructions?
= stressed patient may not remember instructions
= language issues may prevent proper understanding - multilingual options, large print options
= contact number for patient issues with the medicine
= legal protection is post-treatment course questioned
What advice should you give to patients about taking prescribed medications?
= take drugs at correct time and finish the course
= unexpected reactions: STOP and contact prescriber
= known side- effects should be discussed e.g. metronidazole and alcohol
= keep medicines safe: especially from children
What are the 4 main modes of action for drugs?
= activation or blocking of receptors
= activating or blocking enzyme function
= opening or blocking ion channels
= facilitation or blocking transport systems
In a receptor, what do agonists and antagonists do?
= agonist is a drug which causes a reaction to happen
= an antagonist prevents the action from happening
How do ion channels open?
through their natural activity
Give 1 example of ion channels being opened?
through electrical nerve conduction and change the polarity of the membrane
How can ion channels be blocked?
Ion channels can be blocked by molecules moving into the channel or through modulators which work within the channel itself to increase or decrease the opening
How to enzymes work as a method of drug action?
= enzymes are proteins which will act upon a substrate to produce a metabolite or a selection of metabolites or perhaps several metabolites as part of their normal action -> they then return to their original state ready to carry out that action again.
How do transport systems work?
Transport systems work by moving drugs from one part to another and these can be interfered with by inhibitors or false substrates
What must happen after a drug/receptor interaction has taken place?
some mechanism within the cell must exist to change that receptor binding into an action within the cell (often through proteins called G-proteins which will then couple receptor to ion channel or enzyme)
What will allow change to happen in the cell membrane?
action of receptor being changed in shape, cascades through to g protein in cell to allow change to happen in cell membrane