dh206: pharmacology chapter 18: adrenocorticosteroids lisa mayo, rdh,bsdh copyright © 2011, 2007...

DH206: PharmacologyChapter 18: Adrenocorticosteroids

Lisa Mayo, RDH,BSDHCopyright © 2011, 2007 Mosby, Inc., an affiliate of Elsevier. All rights reserved.

Copyright © 2011, 2007 Mosby, Inc., an affiliate of Elsevier. All rights reserved.

Chapter 19 OutlineA&P ReviewHormone SecretionClassificationRoute of AdministrationMechanism of ActionPharmacological EffectsAdverse Rxns


AdrenocorticosteroidsUse in dentistry

Topically or systemically Treatment of oral lesions associated with

inflammatory disordersLong-term therapy: asthma or arthritis


A&P Reviewhttp://www.youtube.com/watch?v=fF_3mJV3Yh0


A&P ReviewAdrenal glands located on upper

surface of each kidneyOuter (next slide) & Inner layerInner layer (adrenal medulla)

Secretes catecholamine’s during fight-or-flight response

Epi is ONLY produced from the adrenal medulla = responsible for converting stored glycogen to glucose (glycogenolysis)


A&P ReviewOuter part: adrenal cortex has 3 layers

Each layer secretes steroid hormones 3 layers of the cortex

Layer of Cortex

Location

Hormone released

Function

Glomerulosa

Outer Aldosterone(mineralcortico-steroid)

Acts on kidney to ↑ absorption Na+, dump K+ & H+

Fasciculata Middle Cortisol Signals to body to ↑ glucose through gluconeogenesis or glycogenolysisBody secretes 20mg/day

Reticularis Inner Sex androgens (testosterone)

Male secondary characteristicsWomen’s only source of androgens


A&P ReviewDeficiency/Adrenal gland not working properly: Addison’s disease

Effects from the 3 layers of the adrenal gland1. Aldosterone deficiency: Increase K+, metabolic acidosis

(H+ ↑), ↓Na+

2. Cortisol deficiency: Inadequate secretion of glucocorticoids, decrease glucose – when needed for flight or fight – will not have)

3. Testosterone deficiency Summary of what will happen to patient

Hyperkalemia (↑K+)Low BP (due to Na drop)Metabolic acidosis (H+ ↑)Hypoglycemia (decrease glucose)


A&P ReviewToo much hormone production from adrenal gland: Cushing’s Disease

Too much ACTH hormone from pituitary Your book sometimes calls this Cushing’s syndrome:

syndrome and disease are very different. Syndrome usually occurs due to exogenous steroid use

Will see the opposite effects as Addison’s Aldosterone: Decrease K+, H+, ↑Na+(↑ BP) Cortisol: Hyperglycemia Testosterone ↑ (secondary male characteristics) –

exogenous steroids can do this as well


A&P ReviewHypothalamic-Anterior Pituitary Axis

A complex set of direct influences & feedback interactions among 3 endocrine glands1. Hypothalamus2. Pituitary gland3. Adrenal gland

Pituitary gland Often called the “master gland” of the endocrine

system Controls many other glands 2 lobes Located in the brain, attached to the hypothalamus

Hypothalamus controls the pituitary gland: connected by the portal system called Hypothalamic-Ant Pit Axis (see net slide)


A&P ReviewHypothalamic-Anterior Pituitary Axis

Hypothalamus releases hormone CRH↓

Acts on Pituitary gland↓

ACTH hormone released↓

Influence adrenal gland↓

Adrenal gland releases its 3 hormones (aldosterone, cortisol, androgens)

Can also have a NEGATIVE FEEDBACK to help regulate hormone levels

SUMMARY: corticosteroids from adrenal gland controlled by hypothalamus & pituitary gland


Hypothalamus stimulates release of hormones that affects many body organs


Hormone SecretionKey Points

More cortisol & CRH are secreted during waking hours

When stressed – body needs more cortisol to copeWhen level of cortisol rises above normal:

ACTH/CRH release is inhibited: called NEGATIVE FEEDBACK

Steroids act like endogenous cortisol – they inhibit release ACTH/CRH Long-term steroid use – ACTH release is

suppressed for long periods thus atrophy occurs to adrenal gland

If steroid is stopped abruptly – relative steroid deficiency result – leads to adrenal crisis


DRUG CLASSIFICATION

MineralocorticoidsGlucocorticoids


Classification1. Glucocorticoids

Stimulate gluconeogenesis (make glucose) & lipolysis (fat breakdown)

Inhibit glucose uptake by cells (to increase blood plasma glucose)

Tx of inflammatory or allergic conditions (Book focuses on this category) – NEXT SLIDE

Drugs called corticosteroids

2. Mineralocorticoids (Aldosterone) Affect kidney: water & electrolyte composition Act on kidney in Loop of Henle Useful for patient with kidney issues Protype: fludrocortisone(Florinef)


Glucocorticoid UsesMEDICAL USES DENTAL USES

Asthma Oral lesions

RA Aphthous stomatitis

Lupus TMD

Addison’s Post-op surgery

Allergy Burning tongue

Transplant rejection Lichen planus

GI disorders (ulcerative colitis, Crohns, IBD)


Glucocorticoid UsesAntiinflammatory Suppress immune responses Palliative rather than curative


Glucocorticoid AdministrationTopical

Useful for dental lesionsOralParental (IM, IV)


Mechanism of Action CorticosteroidsMost potent antiinflammatory agents availableAlmost every cell in the body has glucococortoid

receptors located in the cytoplasmCortisol (glucococortoid hormone) is hydrophobic –

requires active transport into a cell by a proteinOnce inside the cell – travels to nucleus & binds to

DNA

See next slide for picture


Active Transport


Mechanism of Action Corticosteroids

Once inside cell 1. Controls rate of PRO synthesis 2. Controls release of histamine

Immunological Effects ↑ neutrophils ↓ inflammatory agents (prostaglandin, leukotriene,

macrophages)


Corticosteroid Drugs

Classified by duration of action – need to know which drugs fall into each category

p. 217, Table 18-2 Do NOT use this list, use next slide drugs..mistake in your book with Prednisone (listed as short-acting but is intermediate)


Corticosteroid DrugsShort-ActingCortisone(Cortone)

Hydrocortisone(Cortisol, Cortef)

Intermediate-Acting (Useful in Dentistry)

Methylprednisolone(Medrol)

Prednisolone(Orapred, Prelone)

Prednisone(Meticorten, Deltasone) 1st line drug

Triamcinolone(Aristocort, Kenacort)Long-ActingBetamethasone(Celestone)

Dexamethasone(Decadron)

No contraindications

for EPI in LA


Adverse RxnsRare in short-term useLong-term has many side effects due to

suppression of adrenal gland functionMetabolic changes (NBQ)

Moon faceBuffalo humpObesity, Weight gain


Adverse RxnsHyperglycemia (NBQ)HypertensionOsteoporosisMood/behavior changesPoor-delayed healingImmune suppression: Candidiasis,

etc…Peptic ulcers

Corticosteroids ↑production of stomach acid & pepsin

No Aspirin & NSAIDs


Adverse RxnsAdrenal crisis

Adrenal suppression with prolonged use (adrenal gland told not to release ACTH/CRH because patient getting from external source)

Body cannot respond correctly to stressful situation

Ex: dental phobia – steroid user body will not produce enough cortisol to respond to pt’s increased anxiety – crisis could occurPt may need additional steroids day of appt to

accommodate for this issue (Prednisone most commonly given)


Drug Interactions

Drug interactions due to liver metabolism by the CYP3A4 enzyme

1) Insulin drugs2) Carbamazepine(Tegretol)3) Phenytoin(Dilantin)4) Rifampin (TB drug)5) Phenobarbital

dh206: pharmacology chapter 18: adrenocorticosteroids lisa mayo, rdh,bsdh copyright © 2011, 2007...

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