pharm & dental patient Flashcards
As a dentist what drugs do we need to give patients?
- Analgesics{Pharmacogenetics}
- Sedation drugs
- Antibiotics
- Local anaesthetics
- Vasoconstrictors
Name the most common type of odontogenic pain
Acute pain
Name three pain receptors
- Bradykinin2. Prostaglandins 3. Substance P
What are Bradykinin released by?
Blood plasma
What are Prostaglandins released by?
By damaged cells
What is substance P released by?
nociceptors (sensory neurones)
Where do messages from the nociceptors travel to?
From the spinal cord to the thalamus
What happens to pain impulses at the thalamus?
They are distributes to various higher centres Some also go to the reticular formation (governs alertness) and to the amygdala (a part of the limbic system involved in emotion)
What governs alertness?
The reticular formation
The amygdala is part of what?
a part of the limbic system involved in emotion
Name the most common type of analgesics used in dentistry
Non-opioid analgesics are the most common
What are Non-opioid analgesics used to treat?
They are drugs used to relieve tooth ache or pain following dental treatment
Give examples of non-opioid analgesics
- Ibuprofen2. Paracetamol (acetaminophen)3. Aspirin (acetylsalicylic acid)
What is an occasional side effect of ibuprofen?
Xerostomia that may increase oral plaque and dental caries
Give examples of some types of analgesics
- Corticosteroids2. Non-opioid analgesics3. Narcotic analgesics
Name some Corticosteroids
Orabase-HCAOracortOralone
What are Corticosteroids?
They are anti-inflammatory medications the are used to relieve discomfort and redness of the mouth
Give examples of Narcotic analgesics
Codeine Hydrocodone (Vicodin)
What are Narcotic analgesics used for?
For severe pain conditions
What is pharmacogenetics concerned with?
Pharmacogenetics is concerned with the identification of genetic variants that affect the responses to medications in patients
Why is pharmacogenetics important?
As some drugs work more or less effectively in some people than they do for others
What is codeine?
Codeine is an opiate used to treat mild to moderate degrees of pain.
Where is codeines active metabolite?
morphine
Where is codeine covered into its active metabolite?
In the liver
What is the catalysis for the conversion of codeine into morphine?
CYP2D6
What is a pro drug?
An inactive drug that must be metabolised to active drugs within the body
Give an example of a prodrug?
Codeine
What can happen if someone is a poor metaboliser of CYP2D6?
They will experience little to no analgesia from codeine since they lack the enzyme to metabolise the drug.
What is the conversion of codeine into morphine called and what type of pathway is it?
O-demethylation conversion| Represents a minor pathway of codeine metabolism (accounting for less than 10% of codeine clearance)
What percentage of the population are poor metabolisers of codeine?
7%-10% Caucasians 3%-6% Mexican Americans 2%-5% African Americans 1% Asians
What does it mean of you are a poor metaboliser of codeine?
It means the drug is metabolised very slowly so they may accumulate to toxic concentrations
What percentage of the population are intermediate metabolisers of codeine?
10%- 15%
What does it mean of you are an intermediate metaboliser of codeine?
It means the patient has a diminished capacity to metabolise drugs Lower than average dosage may be more sufficient to achieve a therapeutic response
What percentage of the population are extensive metabolisers of codeine?
73%- 82%
What does it mean of you are a extensive metaboliser of codeine?
This is the typical rate of drug metabolism
What percentage of the population are ultra rapid metabolisers of codeine?
1%-2% Caucasians 4% North Americans 10% Greeks10% Portugese 20% Saudia 30% Ethopians
What does it mean of you are an ultra rapid metaboliser of codeine?
It means the person has a higher than usual rate of drug metabolism These drugs may not reach therapeutic concentration so the drugs may be ineffective at standard dosages
What did Sindrup’s investigation in the analgesic efficacy and kinetics of a single oral dose of 75 mg codeine show in respect to pain threshold?
They observed that codeine significantly increased pain thresholds to nocioceptive laser stimuli in Extensive Metabolisers but not in Poor metabolisers
What did Sindrup’s investigation in the analgesic efficacy and kinetics of a single oral dose of 75 mg codeine show in respect to morphine conc in urine ?
The study also observed that urine collected from Poor metabolisers had undetectable levels of morphine after a dose of codeine was administered.But when the same dose was given to Extensive Metabolisers, measurable levels of morphine were detectable in their urine
The failure of poor metabolisers to convert codeine into morphine is demonstrated by which other molecules?
hydrocodone and oxycodone.
Which oral lesions are indicated for antibiotic use?
- Periodontal abscess| 2. Acute necrotising ulcerative gingivitis
Which antibiotics are most commonly prescribed by dentist?
Penicillins
Name some Penicillins used ondontogenic infection treatment
- Amoxicillin,2. Penicillin V, 3. Metronidazole4. Amoxicillin/clavulanate
Name the most popular penicillin used in dentistry
Amoxicillin
What are Penicillin V, amoxicillin and amoxicillin/clavulanate used to treat?
For the treatment of odontogenic infections
What is Metronidazole?
It is a nitroimidazole antibiotic medication
What is Metronidazole used to treat?
It is used to treat anaerobic bacteria and protozoa
Name some dental infections that Metronidazole is used to treat
Treatment of dental infection of bacterial origin such as:1. Periapical abscess,2. Periodontal abscess3. Acute pericoronitis of impacted4. Partially erupted teeth
What is metronidazole used in conjunction with?
Amoxicillin
What should you not take if you are consuming metronidazole?
Alcohol
Why should you not consume alcohol if you are taking metronidazole?
Is thought to have a disulfiram-like reaction Side effects include:NauseaVomitingFlushing of the skin,Tachycardia Shortness of breathe
What is tachycardia?
Accelerated heart rate
What is disulfiram used for?
It is used to support the treatment of chronic alcoholism by producing an acute sensitivity to alcohol
What characteristics do antibiotic used in short-course antibiotic therapy require?
- Rapid onset of action2. Bactericidal activity3. Lack of propensity to induce resistant mutants4. Easy penetrability into tissues5. Activity against non-dividing bacteria6. Not being affected by adverse infection conditions 7. Administration at an optimal dose8. optimal dosing regimen
What can prolonged courses of antibiotics lead to?
- Normal resident oral/gut flora being destroyed2. Selection of resistant strains3. Colonization by harmful micro-organisms that are not normal residents, e.g. multi-resistant bacteria and yeasts
Name some drugs dental patients may already be taking?
- Antidepressants2. Nitrates3. Antihypertensives4. Opioids 5. Insulin6. Steroids7. Beta blockers8. Monoamine oxidase inhibitors 9. Warfarin 10. Antiplatelet drugs11. Biphosphonates
What do antidepressants block?
They block the action of the neurotransmitter acetylcholine
Name a function on acetylcholine
To control the function of the gastrointestinal tract
What happens if you block acetylcholine?
It reduces the production of mucous and saliva leading to dry mouth
What happens if xerostomia is untreated?
Can lead to:Rampant tooth decayPeriodontal disease Bad breathOral yeast infection
Why is saliva important in the mouth?
It protects the mouth by neutralising acids and providing lubrication Saliva also has antibacterial properties
What are nitrates used to treat?
They are used to prevent and relieve chest pain (angina) due to coronary artery disease
What class of medications do nitrates fall in?
Vasodilators as they widen blood vessels
Name the most common type of nitrate
Nitroglycerins
What is the most common side effect of nitrates?
A throbbing headache (in about 50% of people) that radiates towards the forehead, the jaw, the throat, the ear, to the back of the head, or, in rare cases, to the neck and to the shoulder
What is postural (orthostatic) hypotension?
It is an excessive fall of blood pressure when an upright position is assumed
What are some symptoms of postural (orthostatic) hypotension?
FaintnessLight-headednessDizzinessConfusionBlurred vison
What is the most common cause of chronic orthostatic hypotension?
Age related in BP regulation Vasodilation from antihypertensive drugs Autonomic dysfunction
What promotion of elderly patients suffer from postural hypotension?
a quarter
What are Opioid analgesics used to treat?
Used to treat chronic orofacial pain that is refractory to most non-opioid therapy
What is a potential risk of undertaking long term opioid therapy?
Potential risk for developing opioid tolerance, dependence or addiction
What is the primary oral effect of heroin?
Dental decay
What do Heroin addicts, and abusers of other drugs often have?
Poor dental health due to neglect
What do people with diabetes have a higher risk of having?
- Dry mouth2. Gum inflammation 3. Poor healing of oral tissues4. Thrush
What are thrushes?
yeast thrives on the high levels of sugar in the saliva of people with uncontrolled diabetes
What is the most common complication of diabetes therapy in dentistry?
A hypoglycaemic episode| A severe decline in blood glucose level
How can oral infections or dental procedureS affect diabetes?
Can affect food intake in diabetics
Why have Synthetic corticosteroids been developed?
Have been developed for their anti-inflammatory and immunomodulatory effects
Give an example of Synthetic corticosteroids?
Dexamethasone
What risk do patients on steroids present in the dental surgery?
Increased risk of complications because of:1. Adrenal suppression caused by steroid therapy2. Disease or condition which required them to take steroids3. Long-term and other side-effects of steroid therapy
What can chronic usage of steroid inhalers increase your risk of getting?
Oral yeast infections and blood blisters
Why are beta blockers used?
They are used for their ability to block sympathetic influences on cardiac β1 adrenoreceptors
What do patients medicated with non-selective β-blockers have?
A heightened sensitivity to the systemic effects of vasopressors
What do patients medicated with non-selective β-blockers have a higher risk of having ?
An acute hypertensive episode if they receive vasopressors contained in local anaesthetics, e.g. epinephrine
What are some side effects of beta blockers?
They can decrease hepatic blood flow and/or inhibit hepatic enzymes, resulting in the reduced metabolism of lidocaine (local anaesthetic)May lead to increased serum levels and, possibly, toxicity of lidocaine
What can concomitants administration of beta blockers and lidocaine result in?
Myocardial depression
What are monoamine oxidase inhibitors?
They were the first class of drugs used to treat depression
What do monoamine oxidase inhibitors do?
They elevate norepinephrine and serotonin levels by limiting their oxidation by the enzyme monoamine oxidase (MAO)
What is a major drawback of taking monoamine oxidase inhibitors
Is a potential for drug interactions, many of which precipitate an acute hypertensive crisisPotential for an interaction between monoamine oxidase inhibitors and vasoconstrictors to cause acute hypertensive crisis
What a potential side effect of monoamine oxidase inhibitors?
Can cause acute hypertensive crisis
What is warfarin?
Warfarin is an anticoagulant which inhibits synthesis of the vitamin K-dependent coagulation factors II, VII, IX and X
What percentage of the UK population take warfarin?
0.5%-1%
What is used to express the activity of warfarin?
The international normalised ratio (INR)
What is a normal INR number?
1
What happens as the INR number increases?
The risk of bleeding increases exponentially as the INR rises,e.g. INR=5 indicates a high chance of bleeding
When should an INR value be taken and what should it be ideally?
Should be measured within 72 hours prior to the operative procedureINR value must be below 4.0
What are Bisphosphonates used for?
They are used to prevent bone resorption in osteoporosis and bone cancer
What are Bisphosphonates used in association with?
Bisphosphonate-associated osteonecrosis of the jaw (BON)
What is osteonecrosis of the jaw?
Exposire of dead bone in the jaw
What can happen if you suppress bone resorption?
Any damaged bone will be left in situ instead of being resorbed
What complications can Bisphosphonates have?
Leads to surgical complication in the form of impaired wound healing following oral or periodontal surgery or endodontic therapy
What are some common drugs people can have allergic reactions to?
Additives (sulphites or parabens| Epinephrine
What is Stevens-Johnson syndrome ?
Hypersensitivity complex that affects the skin and the mucous membranes
What can begin to form is a patient has Stevens-Johnson syndrome?
Ulcers and other lesions begin to appear in the mucous membranes, almost always in the mouth and lips
What can ulcers and other lesions caused by Stevens-Johnson syndrome result in?
They are usually extremely painful and reduce a patients ability to eat or drink
Which pain receptor is released by the blood plasma?
Bradykinin
Which pain receptor is released by damaged cells?
Prostaglandins
Which pain receptor is realised by nociceptors?
Substance P
If a patient came in complaining of discomfort and redness of the mouth what type of medicine would you recommend?
Corticosteroids
What are nociceptors?
Sensory neurones
The reticular formation governs what?
Alertness
Which type of drug is most commonly used to relieve tooth ache and pain?
Non-opioid analgesics
If a patient comes in with severe pain what could you prescribe them?
Narcotic analgesics
What is Amoxicillin used in conjunction with?
metronidazole
What word is used to describe a drug that is inactive and must be metabolised to become active?
A prodrug
Who would you not prescribe codeine to?
Someone who doesn’t possess the CYP2D6 enzyme as they will not be able to metabolise codeine
Name the antibiotics used to treat odontogenic infections
- Penicillin V, 2. Metronidazole3. Amoxicillin/clavulanate
Which antibiotic is usually used to treat anaerobic bacteria and protozoa and dental infections with bacterial origin?
Metronidazole
Patients with chest pain due to coronary artery disease can be given what?
Nitrites
Name the syndrome associated with hypersensitivity complex that affects the skin and the mucous membranes?
Stevens-Johnson syndrome
What is nitrous oxide and when was it first discovered?
Nitrous oxide is a colourless, almost odourless gas, that was first discovered in 1772 by Joseph Priestley (from Birstall, near Leeds
Who discovered the advantages of nitrous oxide for inhalation sedation?
1844- Horace Wells discovered the advantages of nitrous oxide for inhalation sedation
1845- Wells demonstrated his discovery of the effects of N2O at Harvard Medical School
A patient was given N2O and a tooth was extracted, but during the demonstration the patient complained that he felt some discomfort
Even though the experiment had been successful, the suspicious audience booed Wells from the stage
What is the main use for N2O
The main use for N2O is usually as a mild sedative and analgesic
It helps to allay anxiety that many patients may have, and it offers some degree of painkilling ability
After N2O sedation when can patients leave ?
15 mins
What are the 4 levels of sedation after initial light headedness
- a tingling sensation, especially in the arms and legs, or a feeling of vibration (“parasthesia”)
- warm sensations
- a feeling of well-being, euphoria and/or floating
- sleepiness, difficulty in keeping one’s eyes open or speaking
What is intravenous sedation
Intravenous sedation using a single drug technique is recommended for the majority of adult patients
Benzodiazephine midazolam is favoured
How does Benzodiazephine midazolam
It has a fast onset, providing signs of sedation within one to two minutes
The drug works by slowing down both the heart rate and rate of breathing (CNS depressant)
Half life of midazolam
Relatively short, quick recovery, can leave 1-1.5 hours after
Midazolam not recommended for?
Pregnant and breastfeeding
Can midazolam become addictive?
Like other benzodiazepines, if administered repeatedly, it can become addictive, and if then stopped abruptly it lead to symptoms of withdrawal
What effect does benzodiazepine have on neuro transmitter GABA
Benzodiazepines enhance the effect of the neurotransmitter GABA at the GABAA receptor,
resulting in sedative, hypnotic (sleep-inducing), anxiolytic (anti-anxiety), euphoric, anticonvulsant, and muscle relaxant properties
What is the likelihood of respiratory depression/ arrest w midazolam
The incidence of respiratory depression/arrest is low (0.1-0.5%) when midazolam is administered alone at normal doses
What has midazolam recently been used in?
executions by lethal injection in the USA in combination with other drugs
What is a pulse oximeter?
Pulse oximeter: medical device that indirectly measures the oxygen saturation of a patient’s blood and changes in blood volume in the skin
Is midazolams rapid disappearance from the blood associated w rapid recovery?
NOUUURUURRR444RRRRR
What are the 2 phases of patients recovering from midazolam sedation
- Recovery from sedation (“street fitness”)
- Recovery from psychomotor impairment
After midazolam, what is not recommended?
Driving or operating machinery for 24h after operation
Why is prescribing antibiotics by dentists become an important aspect of dental practice
Most oral facial infections originate from ontogenic infections
What percent of common antibiotics get presented by dentists?
7-11%
In the UK what % of dentists accounted for community (non-hospital) prescriptions of antibiotics
7%
Acute and chronic infections of pulpal origin are solved how?
Operative intervention, not antibiotics
