Tag: Pharmacology

CORTICOSTEROIDS IN DENTISTRY

Dr.Mehnaz1 Comment

🔷 Introduction:

Steroids are a group of hormones produced naturally in the body.

The adrenal cortex consists of 3 zones:

  1. Zona Glomerulosa synthesizes Aldosterone, the most potent Mineralocorticoid in humans.
  2. Zona Fasciculata – produces hydrocortisone (a glucocorticoid)
  3. Zona Reticularis produces Adrenal Androgens

• Glucocorticoid secretion is regulated by ACTH produced in the anterior pituitary. Cortisol has a -ve feedback on ACTH production.

• In Addison diseases, Glucocorticoid secretion impaired & ACTH is ⬆️

🔷 Corticosteroid Action & its regulation

  • Glucocorticoid – Hepatic Glycogen deposition
  • Mineralocorticoid – Sodium, electrolyte-fluid balance.
  • Glucocorticoid play critical role in body’s response to stress.

Stress

⬇️

Release of cytokines (IL-1)

⬇️

⬆️ cortisol levels

🔷 Classification:

Adrenocortical Hormones & Related Drugs

🔷 Steroid synthesis:

The substrate for steroid production is cholesterol. It is mobilized from the outer to the inner mitochondrial membrane by the steroidogenic acute regulatory (StAR) protein.

🔷 Glucocorticoids:

1) Hydrocortisone

• Action: Anti-allergy, anti-inflammatory

• Therapeutic Uses:

a) OSMF
  • intralesional injection in dose of 20-50 mg/mL
  • Topical application
  • Tablet in dose of 100mg/day can be given systemically to relieve burning sensation.
  • Tab. Cortisol(25mg) combined with dexamethasone(90mg) can be given at biweekly interval.*

Action: Fibrinolytic,Anti-allergic, anti-inflammatory*

It causes ⬇️ fibroblastic production & deposition of collagen*

b) Aphthous ulcer:
  • Topical application with orabase
  • Intralesional injection of hydrocortisone acetate (25mg/ml)
c) Desquamative Gingivitis:
  • Topical application (0.25-0.5%) to the affected area
d) Osteoarthritis
  • Intra-articular injection (25mg/ml)
e) Addisons disease
  • 20-30mg/day in divided doses
f) Lichen planus, pemphigus & eczematous skin disease
g) Shock, status asthmaticus, ulcerative colitis

• Trade Name: CORTEF, ORABASE-HCA

• Preparation:

  1. Oral: 5 – 20 mg tab.
  2. Topical – 1% eye drop solution; 0.025 nasal drops, 0.25-2.5% skin creams

• Hydrocortisone acetate 25-50 mg/mL for soft tissue suspensions

• Hydrocortisone sodium phosphate: 50mg/mL IV, IM, SC

2) Cortisone:

• Uses:

  1. OSMF
  2. Addison disease
  3. Hodgkin lymphoma

3) Prednisolone:

• Action: Anti-allergic, anti-inflammatory, immunosuppressive

• Uses:

  1. Rheumatoid arthritis: 10mg/day in divided doses
  2. Collagen disease: 1mg/kg
  3. SLE: IM/IV; Topical application 2-3 times daily
  4. Leukemia: ALL as maintenance dose
  5. Erythema multiforme, pemphigus, bullous pemphigoid, behchet’s syndrome
  6. Bronchial asthma: 40-60 mg
  7. Post-herpetic neuralgia
  8. Amyloidosis, cyclic neutropenia, purpura

• Trade name: DELTA-CORTEF, PRELONE

4) Triamcinolone:

• Uses:

  1. Lichen planus: Topical application 3-4 times daily
  2. Erythema multiforme: 40-100 mg/day or inhalation doses
  3. Recurrent aphthae: Oral (2-4 mg/day)
  4. Desquamative gingivitis, OSMF, contact chelitis – intralesional (2-3 mL/day)

• Trade name: Kenolog cream

5) Dexamethasone:

• Uses:

👉🏻Mainly used for adrenal cortical suppression

  • Allergic diseases, serum sickness, urticaria, hay fever, angioneurotic edema: IV; topically 2-4 times a day
  • Benign migratory glossitis: Topical application
  • Shock, cerebral edema, occular diseases.

• Trade name: DECADRON

6) Betamethasone:

• Action: Anti-allergy, anti-inflammatory

• Uses: Lichen planus, pemphigus, Aphthae ulcer

Dr. Mehnaz Memon🖊

References: Self Notes, Image chart source: Classification of Drugs with DOC by Vikas Seth (Third Edition)

CHOOSING APPROPRIATE ANTIBIOTIC

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Antibiotics can be divided into 2 classes based on their mechanism of action:-

  • Bactericidal
  • Bacteriostatic

➡️ Bactericidal antibiotics kill bacteria by inhibiting cell wall synthesis. Example:

  • Beta-lactams (Penicillins, Cephalosporins, Carbapenems, Monobactams)
  • Glycopeptides viz. Vancomycin
  • Aminoglycosides
  • Fluoroquinollines
  • Others: Bacitracin, Cycloserine, Metronidazole

➡️ Bacteriostatic antibiotics limit the growth of bacteria by interfering with bacterial protein production, DNA replication or other aspects of bacterial cellular metabolism.

They must work together with immune system to remove the micro-organisms from the body. Example:

  • Tetracyclins
  • Sulphonamides
  • Macrolides
  • Lincosamides
  • Chloramphenicol
  • trimethoprim

Most antimicrobial agents in clinical use are bactericidal,

Note that while it is rational to favor bactericidal agents over bacteriostatic agents, neither has ever been shown to be superior (probably because true recovery from infection cannot occur until the body is able to mount an appropriate immune response, thus “buying time” may be just as good as active killing)

Minimum inhibitory concentration (MIC) versus minimum bactericidal concentration (MBC).

➡️ The MBC is the minimum concentration of drug which can kill the micro-organisms.

➡️ The MIC is the minimum concentration of drug which can inhibit the growth of micro-organisms.

🔷 CHOOSING APPROPRIATE ANTIBIOTIC (A Clinician’s guide to the CARAT criteria)

Council for Appropriate and Rational Antibiotic Therapy (CARAT) criteria for accurate use of antibiotic therapy
● Evidence-based results ●Therapeutic benefits
● Safety
● Cost-effectiveness
● Optimal drug dose and duration —Shorter-course, more aggressive therapy

(i) Evidence-based results:

In choosing an antibiotic, clinicians should consider the clinical evidence demonstrating that the drug is clinically and microbiologically appropriate, the efficacy of that drug in well-designed clinical trials, and the antibiotic resistance patterns of the local region. Clinicians should then use their professional judgment to choose the optimal antibiotic.

(ii) Therapeutic benefits:

If possible, the clinician should identify the causative pathogen and use surveillance data on regional antibiotic resistance patterns in selecting the optimal therapeutic agent.

(iii) Safety:

In treating patients with a particular drug, safety must be weighed against efficacy. Clinically applicable treatment strategies should be chosen to maximize efficacy while minimizing side effects.

(iv) Optimal drug for optimal duration:

Optimal drug selection requires finding the antimicrobial class and the specific member of that class that is best suited to treat a particular infection. Because empiric therapy is necessary in most cases, multiple factors have to be considered. Among these are whether the etiologic agent is likely to be gram-positive or gram-negative, whether a narrow or broad-spectrum agent should be chosen, the resistance patterns of the likely pathogen to this drug, both nationally and regionally, and the individual patient’s medical history, including recent antibiotic exposure.

Optimal duration means prescribing the selected drug for the shortest amount of time required for clinical and micro- biologic efficacy. There are many reasons for reducing an- timicrobial therapy to the shortest appropriate duration. They include the potential for reduced occurrence of adverse effects, increased patient adherence, decreased promotion of resistance, and decreased costs.

(v) Cost-effectiveness:

Choosing inappropriate therapy is associated with increased costs, including the cost of the antibiotic and increases in overall costs of medical care because of treatment failures and adverse events.

Dentowesome | @drmehnaz🖊

References:

  1. https://www.amjmed.com/article/S0002-9343(05)00381-5/pdf
  2. https://microbeonline.com/minimum-inhibitory-concentration-and-minimum-bactericidal-concentration-mbc/

ANALGESICS AND ANTI-INFLAMMATORY DRUGS(NSAID’s) IN DENTISTRY

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💊Analgesic is a drug that selectively relieves pain by acting in the CNS or on the peripheral pain mechanisms without significantly altering consciousness.

💊They are divided into 2 groups:

  1. Opiod/Narcotic/Morphine like
  2. Non-opiod/Non-Narcotic/antipyretic (Aspirin like drugs)

The antipyretic analgesics & NSAID’s are more commonly employed for dental pain because tissue injury and inflammation due to abscess, caries, tooth extraction etc. is major cause of acute dental pain.

🔆 CLASSIFICATION:

Image: 1
Image: 2

🔆 ANALGESIC/NSAID’s IN DENTISTRY:

  • The antipyretic analgesics used mainly for dental pain is Paracetemol.
  • Paracetemol (Acetaminophen) is most frequently used to relieve toothache in Pregnancy. It has week anti-inflammtory effect & causes no teratogenesis in the developing fetus.
  • Pain during invasive dental procedures is alloyed by a local anesthesic before & after is treated with NSAID’s.

💊 NSAID’s use during Pregnancy: (The devastating effects to the infant) 👇🏻

Image: 3

🔆Use of OPIOIDS in Dental Pain:

  • Less used than analgesics
  • Mostly codeine is used for dental patients because other opioids cause dullness & short lasting pain.
  • Other alternative Opioid Analgesics used are – Tramadol, Pentazocine.

💊MORPHINE – Depressant actions‼️

🔻Adverse effects:
  1. Sedation, mental clouding, lethargy, nausea, vomitting, diarrhoea.
  2. Respiratory depression, blurring of vision.
  3. Allergic conditions, rashes, urticaria, itching, swelling.
  4. May develop tolerance & dependance.
🔻Contraindications:
  1. Urinary retention – infants & elderly
  2. Asthma patients
  3. Hypotensive states
  4. Hypovolaemic states

💊NSAID’s :

  1. Analgesic, antipyretic, anti-inflammatory effect.
  2. Effectively relieves inflammatory tissue, injury related pain, signs of inflammation like pain, tenderness, swelling are suspected.
  3. Cellular metabolism is increased & due to increased Glucose utilization there is decrease in blood sugar.
  4. Has teratolytic & mild-antiseptic properties
  5. Irritates gastric mucosa
  6. Interferes with platelet aggregation & bleeding time prolonged.
🔻Adverse effects:
  • Nausea, vomiting, diarrhoea, blood loss in stools.
  • Haemolysis in G6PD deficient patients.
  • Nephrotoxicity & hepatotoxicity in long term use.
  • Allergic reactions – rashes, urticaria, photosensitivity.
  • Pregnancy & Infancy – Refer Image 3
🔻Contraindications:
  • Nursing and pregnancy
  • Serious bleeding
  • Allergy/Asthma/Angioedema
  • Impaired renal function
  • Drug (anticoagulant)

Dr. Mehnaz Memon🖊

References:

  1. Flowcharts: Classification of Drugs with DOC by Vikas Seth (Third Edition)
  2. KD TripathiEssentials of Medical Pharmacology 7th Edition; Internet

Drugs of choice in respiratory diseases

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🔗Refer Asthma First Aid & Prevention tips on Page 2‼️

ASTHMA

Mild intermittent
DRUG OF CHOICE

💊 Short acting β2-agonists (e.g. Salbutamol, Terbutaline) inhalations when needed.

Alternative drugs/Treatments

💊 Anticholinergics (e.g. Ipratropium, Tiotropium) inhalations when needed, alone or in addition to beta-2 agonists

Comments‼️

💬 Patient is asymptomatic between the dyspnoea episodes, so no daily medication required!

ASTHMA

Mild persistent
DRUG OF CHOICE

💊 Short acting β2-agonists (e.g. Salbutamol, Terbutaline) inhalations ➕ Corticosteroid inhalation (low dose)

Alternative drugs/Treatments

💊 Short acting β2-agonists ➕ Mast cell stabilizer or Leukotriene antagonist or Theophylline sustained release

Comments‼️

💬 Beta-2 agonist inhalation is needed every day, so once daily corticosteroid inhalation if given for asthma control.

ASTHMA

Moderate persistent
DRUG OF CHOICE

💊 Long acting beta-2 agonists (e.g. Salmeterol, Formeterol) inhalations ➕ Corticosteroid inhalation (low to high dose)

Alternative drugs/Treatments

💊 Long acting beta-2 agonist tablets or Theophylline sustained release ➕ Corticosteroid inhalation (medium dose)

Comments‼️

💬 The dose of corticosteroid inhalations depends on the severity of symptoms.

ASTHMA

Severe persistent
DRug of choice

💊 Long acting beta-2 agonists (e.g. Salmeterol, Formeterol) inhalations ➕ Corticosteroid inhalation (high dose) ➕ Corticosteroid tablets/syrup

Alternative drugs/Treatments

💊 Long acting beta-2 agonist tablets or Theophylline sustained release ➕ Corticosteroid inhalation (high dose) ➕ Corticosteroid tablets/syrup

COMMENTS‼️

💬 Systemic corticosteroids have significant adverse effects, so after adequate asthma control, are gradually withdrawn.*

ASTHMA

Acute severe asthma
drug of choice

💊 Oxygen 60% ➕ Nebulized beta-2 agonists (e.g. Salbutamol) in high dose ➕ Systemic corticosteroids

comments‼️

💬 An emergency condition, earlier called as status asthmatics. Aminophylline is no longer recommended.

* After adequate control of severe persistent asthma, systemic corticosteroids are withdrawn, and the patient then would be managed as moderate persistent type. This is called "step down" approach of management. In this approach, it is considered better to manage patients assuming in the next higher type and then, after reviewing in 1-6 months, to step-down, instead of "step-up" after failure in asthma control.

Aspirin induced

asthma
DRUG OF CHOICE

💊 Leukotriene antagonists (e.g. Montelukast, Zafirlukast)

Exercise induced

asthma
DRUG OF CHOICE

For Prophylaxis: Mast cell stabilizers or beta-2 agonists or Leukotriene antagonists💊

COPD

DRUG OF CHOICE💊
  • For smoking cessation: I line: Behaviour therapy; II line: Nicotine replacement therapy; III line: Antidepressants e.g. Bupropion
  • For respiratory infections: Antibiotics
  • For bronchodilatation: I line: Anticholinergics; II line: beta-2 agonists; III line: Theophyline
  • For hypoxemia: I line: Ambulatory oxygen; II line: Long term oxygen therapy

Dry cough

DRUG OF CHOICE

💊 Cough suppressants (e.g. Dextromethorphan) + Treat the cause e.g. post nasal drip by antihistaminics and decongestants.

Productive cough

DRUG OF CHOICE

💊 Expectorants (e.g. Pot iodide) &/or Mucolytics (e.g. Acetylcysteine) ➕ Treat the cause e.g. allergy by antihistaminics and bacterial infection by antibiotics

References: CLASSIFICATION OF DRUGS WITH DRUGS OF CHOICE 3RD EDITION BY VIKAS SETH

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Bisphosphonates

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Bisphosphonates are first-line drugs used to treat a wide range of bone disorders, including:

  • Osteoporotic fragility fractures
  • Paget’s disease of bone
  • Certain cancers – where they are used to prevent pathological fractures

Bisphosphonates are easily identifiable drugs, too. They all contain either of the following two suffixes – –dronate or –dronic acid.

Mechanism of Action

Bisphosphonates act on bone – where they inhibit cells called osteoclasts.

The function of osteoclasts is to break down bone, an essential function for the bone maintenance and repair. However, in diseases such as osteoporosis, osteoclasts can play a pathological role and so, by intervening in how osteoclasts work, it can reduce bone loss and improve bone mass.

Bisphosphonates have a similar structure to naturally occurring pyrophosphate and so are readily absorbed into bone. There, bisphosphonates accumulate in osteoclast cells – triggering cell death. Fewer osteoclast cells lead to reduced bone turnover and an increase in bone mass and reduction in bone loss.

Side Effects

One of the most common side effects of orally administered bisphosphonates is esophagitis – or inflammation of the esophagus. To reduce the risk of esophagitis, patients are counseled to take bisphosphonates in a more cautionary manner compared to other drug classes.

Patients are counselled to take these drugs whilst remaining upright, first thing in the morning and 30 minutes before food/medicines and taken with a full glass of water. Patients should remain upright for 30-minutes post-administration. By taking these steps, the risk of esophagitis or irritation to the esophagus, is substantially reduced.

Other side effects of bisphosphonates include:

  • Hypophosphatemia – low blood phosphorus levels
  • Osteonecrosis of the jaw – a rare effect associated with high-dose IV therapy
  • Atypical femoral fracture
  • Headache
  • Constipation
  • Nausea

Bisphosphonates may also be associated with other side effects not listed in this guide.

Source – PTCB guide to pharmacology

Antimalarial drugs

Gerlyn BraganzaLeave a comment

What is malaria ?

•Malaria is a life-threatening disease.

• It’s typically transmitted through the bite of an infected Anopheles mosquito.

Female anopheles mosquito

•Infected mosquitoes carry the Plasmodium parasite.

•When this mosquito bites you, the parasite is released into your bloodstream.

•Once the parasites are inside your body, they travel to the liver, where they mature. After several days, the mature parasites enter the bloodstream and begin to infect red blood cells.

•Within 48 to 72 hours, the parasites inside the red blood cells multiply, causing the infected cells to burst open.

•The parasites continue to infect red blood cells, resulting in symptoms that occur in cycles that last two to three days at a time.

AREAS WHERE MALARIA IS FOUND –

Malaria is typically found in tropical and subtropical climates where the parasites can live.

Life cycle of malaria

Drugs used in malaria

Source – 1.textbook of pharmacology for dental students tara shanbhag

2. Healthline

3 pinterest and Google images

Therapeutic Uses of Adrenaline

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1) Vascular Uses:

(i) Hypotensive States: (Shock, Spinal Anaesthesia)

➡️ In case of anaphylactic shock or angioedema of Larynx or for bronchospasm attending drug hypersensitivity (Adrenaline + sub-class of gluco-corticoids) is recommended.

  • Put the patient in reclining position, administer oxygen at high flow rate
  • Inject adrenaline 0.5 mg (0.5 ml of 1 in 1000 solution for adult, 0.3 ml for child (6-12 years) & 0.15 ml for child (upto 6 years) i.m
  • Repeat every 5-10 min. in case patient does not improve.
  • This is the only life saving measure
👉🏻 Adrenaline should not be injected i.v unless shock is life threatning. Should be diluted to 1:10,000/1:1,00,000 & infused slowly with constant monitoring

(ii) Along with local anaesthetic:

➡️ Adrenaline 1 in 2,00,000 to 1 in 1,00,000 for infilteration, nerve block, spinal anaesthesia

🔅Effects:

  • Duration of anaesthesia prolonged
  • Systemic toxicity of LA ⬇️
  • Local bleeding minimized

(iii) Control of local bleeding: (Skin, mucous membrane eg. Epistaxis)

➡️ Compresses of adrenaline 1 in 10,000 can control arteriolar & capillary bleeding

2) Cardiac Uses:

🔅Cardiac Arrest (Drowning, Stokes-Adam syndrome)

👉🏻 Adrenaline is used to stimulate the heart, i.v infusion with external cardiac massage

3) Allergic disorders:

  • Adrenaline is a physiological antagonist of histamine which is an important mediator of many acute hypersensitivity reaction
  • Affords quick relief in urticaria, angioedema
  • Ineffective in delayed type allergy because histamine not involved.

4) Mydriatic:

👉🏻 The ester prodrug of adrenaline – Dipivefrine is an adjuvant drug for open angle glaucoma

5) Insulin hypoglycaemia:

👉🏻 Adrenaline can be used as an expedient measure but glucose should be given as soon as possible.

Dr. Mehnaz Memon🖊

References: Essentials of Medical pharmacology, KD Tripathi (7th Ed)