Pharmacology and Therapeutics - Carie Martin

Question 1

What is CKD?

Answer 1

A progressive and irreversible condition

Known as an eGFR of <60ml/min/1.73m2 and/or kidney damage that is present for 3 or more months

Question 2

What molecule is used to measure glomerular filtration rate?

And why?

Answer 2

Creatinine –> A waste product from muscle

It is generated at a relatively constant rate

Mostly removed via filtration

However…. Affected by age, race and weight, and it has a non-linear realtionship with true GFR

Question 3

What equation is used to calculate renal function in order to figure out dosing adjustments?

And what are the downsides of this?

Answer 3

Cockcroft and Gault (CrCl)

Not accurate when the CrCl is less than 20ml/min

Also problematic in those with large body weight/muscle

Question 4

What are some of the causes of CKD?

Answer 4

Diabetes –> Number 1 cause

Hypertension

Previous AKIs

Nephrotoxic drugs

Glomerulonephritis

Reflux neuropathy

Question 5

What are some of the complications of CKD?

Answer 5

Itching –> Due to build up of toxins

Oedema

Nausea

Restless legs and cramps

Electrolyte imbalances

Question 6

Can ACEi be used in CKD?

Answer 6

YES

They are protective in low doses

Contraindicated in AKIs!

Question 7

How do we manage Renal Anaemia in CKD?

Answer 7

Give Erythropoiesis Stimulating Agents (ESAs) and iron (eg, Darbepoetin)

Aim for a Hb level of 10-12g/dL

Question 8

How does Renal Bone Disease occur?

And how is treated?

Answer 8

A reduction in Vit D hydroxylation causes hypocalcemia. This increases parathyroid stimulation, which causes more calcium and phosphate to be released from our bones

Use alfacalcidol 250ng three times week (already hydroxylated vitamin D)

Phosphate binders are also used (eg, calcium carbonate/acetate)

Question 9

What can Uremia cause?

Answer 9

Displacement of drugs from protein binding sites

Eg, phenytoin/diazepam/digoxin/sodium valproate/warfarin

Question 10

What is the effect on insulin in CKD?

Answer 10

Insulin cannot be cleared, so its half-life is increased

So dose requirements are decreased

Question 11

Which types of drugs will have problematic elimination in CKD?

Answer 11

Those that have over 25% excretion (unchanged) in the kidneys

Question 12

Define Frailty

Answer 12

A syndrome of physiological decline in late life, characterised by marked vunerability to adverse health outcomes

People arent always old!!….but more likely

Question 13

What’s the difference between compliance and adherence?

Answer 13

Compliance –> The extent to which the patients behaviour matches the prescriber’s recommendations

Adherence –> The extent to which the patients behaviour matches agreed recommendations from the prescriber

Question 14

Give some examples of intentional and unintentional non-adherance

Answer 14

Unintentional –> Difficulty swallowing large tablets, Memory Problems, Complicated polypharmacy

Intentional –> Lack of confidence in drugs/prescriber, concerns of side effects, lack of information

Question 15

What 5 things are assessed in a NOMAD assessment?

Answer 15

Knowledge

Visual Issues

Manual Dexterity

Cognition

Supply

Question 16

Explain some PK changes that occur in the eldery

Answer 16

Absorption –> Reduced rate, but extent remains unchanged

Distribution –> Increased body fat and less total body water (longer half-life of fat soluble drugs, and increased serum conc of water soluble drugs)

Metabolism –> Reduced albumin (increased free drug conc of protein bound drugs) and muscle mass (increased free conc of muscle bound drugs like digoxin)

Elimination –> Predicatble age related decline in kidney function, which causes accumulation of renally excreted drugs

Question 17

What monitoring must be done for somebody on digoxin?

Answer 17

K+ levels

Due to the possibility of hypokalaemia

Question 18

What is the main aim of osteoporosis managment?

Answer 18

Reduce the risk of fractures (#)

Do this by correcting deficincies in vitamin D and calcium (oral bisphosphonates are first line)

Question 19

How is osteoporosis diagnosed?

Answer 19

A DXA assessment, with a T-score of -2.5 SD

If clincically unsuitable, and over 75, the clinican can assume diagnosis without this assessment

Question 20

What are the levels of calcium and vitamin D that need to be prescribed in the following patients…

Calcium intake is adequate

Inadequate calcium intake

Inadequate calcium intake plus housebond

Answer 20

Adequate intake –> 400units of Vit D

Inadequate –> 400units of Vit D plus 1000mg of calcium OD

Inadequate plus housebound –> 800units of Vit D plus 1000mg of calcium OD

Question 21

When can denosumab be used in osteoporosis?

Answer 21

Secondary prevention of fractures in postmenopausal women who are unable to take alendronate and either riseondronate or etidronate

Question 22

What is the impact of falls in patients?

Answer 22

Fractures

Confusion

Loss of confidence (psychological problems)

Soft tissue injuries

Question 23

What are the 2 classes of drugs that provide the biggest risk of falls?

Answer 23

Drugs acting on the brain (psychotropic drugs)

Drugs acting on the heart and circulatory system

Question 24

When will people be refered to a falls clinic?

Answer 24

If they have frequent falls

Poor balance

Undiagnosed dizziness

Syncope (unknown cause)