Type 2 Diabetes Therapeutics Flashcards
Metformin dosages
500, 850 and 1000mg tablets,
Usually start with 500mg od or bd
Little evidence for > 1g bd
XR tablets 500, 750mg, 1g
liquid formulation: 500mg in 5 ml
Metformin and insulin
Lowers insulin resistance “insulin sensitiser”
By how much does metformin lower HbA1c?
Lowers by 15-20mmol/L
Metformin and weight?
Often lowers weight
Metformin and micro & macrovascular complications
Reduces both (UKPDS)
UKPDS and metformin?
Metformin reduces microvascular and macrovascular complications
Metformin and LDL and triglycerides?
Reduces triglycerides and LDL
Is metformin safe in pregnancy?
Yes:
- pre-existing T2DM
- GD
Metformin and PCOS
Metformin often prescribed to try and prevent diabetes
NAFLD and metformin
You could give metformin in NAFLD. Probably helps because of its insulin sensitising effect etc
Metformin side effects
GI side effects:
Anorexia, nausea, vomiting, diarrhoea, abdo pain, taste disturbance
GI side effects in up to 25%; only 5% cannot tolerate the drug
Interference with vitamin B12 and folic acid absorption (anaemia is rare)
Lactic acidosis
- 1 case per 100,000 treated patients
- Can be fatal
Liver failure
Rash (jennifer lawrence lol)
Metformin and vitamin B12 and folic acid
Metformin can reduced vitamin B12 and folic acid absorption
Other effects:
Lactic acidosis (hyperventilation, confusion, coma)
Rash
Liver failure
Which patients are at high risk of lactic acidosis?
high pre-existing risk eg acute heart failure, sepsis, acute MI, respiratory failure, hypotension for any cause
Metformin and the Liver
-may cause liver failure
-Liver toxicity:
Discontinue if advanced cirrhosis/liver failure
Discontinue if risk of lactic acidosis eg encephalopathy, alcohol excess
May be beneficial in Non-alcoholic fatty liver disease (NAFLD)
Metformin and the kidneys
-Avoid or stop if eGFR 150μmol/l
Half dose if eGFR 30-45 ml/min
Temporarily withhold if IV contrast being used eg. Angiography, CT scan
Which OHA should you temporarily avoid when using contrast? (i.e. angiography, CT scan)
Metformin
At which eGFR value should you half dose of metformin?
30-45ml/min
Stop when below 30ml/min or if serum creatinine >150µmol/L
Sulphonylureas and HbA1c?
Reduce by 15-20mmol/mol by increasing insulin secretion
More rapid reduction in hyperglycemia than insulin sensitizers
Concern re acceleration of beta cell demise
Which reduced hyperglycemia more quickly: metformin or SU’s?
SU’s
Do SU’s reduce micro and macrovascular complications?
Just microvascular
UKPDS and ADVANCE
Which sulphonylureas have the greatest risk of hypoglycaemia?
Older agents e.g. chlorpropramide or glibenclamide
Particular care in elderly/frail, alcohol excess, liver disease
Which types of people should you be especially careful with sulphonylureas?
Elderly/frail people
Alcohol excess
(probably because of increased risk of hypoglycaemia)
Side effects of sulphonyureas?
Hypoglycaemia (be carfeful in oldies, liver disease, alcoholics)
Weight gain
GI upset, headache
Why would Gillian not want to take sulphonylureas?
weight gain mothafukas lol probably also because of hypersensitivity, blood dyscrasias and liver dysfunction and hypoglycaemia and headaches and GI upset
When should you avoid sulphonylureas?
In severe hepatic and renal failure
(metformin should be discontinued in advanced cirrhosis/liver failure, and when eGFR<30ml/min, lactic acidosis, encephalopathy, IV contrast)
Why was rosiglitazone taken off the market?
Increased risk of MI (this was in red in lecture)
Dosage of pioglitazone?
15-45 mg
What receptor do PPAR-gamma agonists bind to? (pioglitazone)
Nuclear receptors
-transcription of certain insulin sensitive genes
Where are PPAR-gamma receptors found?
Mainly adipose tissue but also skeletal tissue and liver
Are TZDs lipophiylic or lipophobic?
Lipophiylic,
don’t even know if lipophobic is a thing lol
Hypoglycaemia with TZDs?
Not if used without SU’s
What is the absolute worse thing about TZDs?
Weight gain almost inevitable
-This is due to increase in subcutaneous fat and fluid retention
REMEMBER OMG this fluid retention almost doubles risk of admission with heart failure
-risk still low if no heart failure pre-existing
TZD’s and heart failure?
Fluid retention results in near doubling of risk of admission with heart failure (risk still low in non-elderly without pre-existing HF)
Prevention of microvascular and macrovascular complications with TZD’s?
No :( but improvement in microalbuminuria :)
Prevention of macrovascular complications:
No, but composite endpoint of all-cause mortality and non-fatal MI reduced (PROactive trial)
Glitazone drugs and risk of hip fracture
Glitazone drugs increase risk of fracture by 20% per year of use
Incretins and blood glucose level?
Incretins decrease the blood glucose level by increasing the amount of insulin released from beta cells
What is dapagliflozin?
SGLT2 inhibitor, also known as Forxiga
Name an SGLT2 inhibitor
Dapagliflozin (Forxiga)
The incretin effect
The incretin effect: Oral glucose load produces a greater insulin response than that of an isoglycemic intravenous infusion
What would you do if you have risk of lacic acidosis (i.e encephalopathy, alcohol excess) and you are on metformin?
Discontinue metformin
- Also discontinue in advanced liver failure/cirrhosis
- temporarily withold if iv contrast is being used e.g. angiogram, CT scan
TZDs and hip fractures?
Increases risk of hip fractures by 20%
How are gliptins cleared?
Kidneys
Where are gliptins secreted?
The intestines
Risk pancreatitis with which diabetes drugs?
GLP-1 agonists
DPP-IV inhibitors
(1/200 risk unless liraglutide 1/100)
Why is a very low energy diet not recommended?
Because after 12 months, change is not very different to just going on a normal diet
Bariatric surgery recommended at which BMI?
BMI>35 is recommendation for surgery in diabetes
-But, need to demonstrate at least 5-10% weight loss before the surgery over 6-12 months
Side effects of GLP-1 agonists
Nausea
Injectable :(
(pancreatitis, pancreatic cancer??)
Why are DDP-IV inhibitors not quite as good as GLP-1 agonitsts?
Less potent than GLP-1 mimetics – can only work on what’s there and GLP-1 levels are low in T2DM
Weight loss in GLP-1 agonists/DPP-IV inhibitors?
Weight loss in GLP-1 agonists but not DPP-IV inhibitors
By how much does an SGLT2 inhibitor reduce sugar uptake?
Reduces sugar uptake by about one quarter
Possible side effects of SGLT2 inhibitors? (because of more sugar in urine)
Thrush
Possible increase in urinary infections
Normal insulin regime for type TWO diabetes
o.d. NPH
If that doesn’t work: b.d. NPH or humulin M3
Which T2DM drug can cause oedema?
Thiazolidinediones
Which molecule binds to SUR-1 subunits to open the KATP channel?
ADP-Mg2+
Tolbutamide, glibenclamide, glipizide
Sulphonylureas
-displace binding of ADP-Mg2+
When do you take glinides?
Just before meals. They prevent the post-prandial rise in blood glucose
Exenatides mimic which type of drug?
GLP-1 agonists
Actions of GLP-1 and GIK
- GLP-1 decreases release of glucagon
- GLP-1 and GIK both increase insulin secretion and delay gastric emptying
Which receptor does exenatide (an incretin analogue) bind to?
Binds to GPCR GLP-1 receptors that increase intracellular cAMP concentration
Exenatide and weight loss?
Modest weight loss, reduces hepatic fat accumulation
How is exenatide administered?
Subcutaneously, twice daily
liraglutide longer lasting, once daily
Side effects of exenatide?
May cause nausea, hypoglycaemia and much more rarely, pancreatitis
Gliptins
(DPP-4 inhibitors)
What is alpha-carbosidase?
A brush border enzyme that breaks down dissacharides and starch into absorbable glucose
Side effects of acarbose?
Adverse effects occur in the G.I. tract – flatulence, loose stools, diarrhoea, abdominal pain, bloating – undigested carbohydrate is welcomed by colonic bacteria!
ON THE PLUS SIDE, NO HYPOGLYCAEMIA fatt
Which cells are predominantly associated with PPARɣ?
Adipocytes
PPARɣ becomes associated with which receptor?
PPARɣ becomes associated with the retinoid receptor (RXR)
Name some of the proteins expressed through PPARɣ-RXR?
Lipo-protein lipase
Fatty acid transport protein
GLUT 4
Lipo-protein lipase, fatty acid transport protein and GLUT 4
PPARɣ-RXR
Insulin independent drugs used in diabetes?
- SGLT2 inhibitors
- alpha carbosidase inhibitors
Insulin dependent drugs?
GLP-1 agonists
DPP-IV inhibitors
Biguanides
Which part of the kidney tubule do SGLT2 inhibitors act upon?
Proximal tubule
Why might blood glucose levels fluctuate widely in a person with diabetes? (nerve)
Autonomic nerve damage
Gastroparesis: persistant nausea and vomitting, bloating and loss of appetite can make blood glucose levels fluctuate widely due to ABNORMAL FOOD DIGESTION
Treatment for gastroparesis?
Metoclopramide, domperidone, erythromycin
Gastric pacemaker
Gustatory sweating
Autonomic neuropathy can affect the nerves that control sweating- prevents the sweat glands from working properly.
The body cannot regulate its temperature as it should. Nerve damage can also cause profuse sweating at night or while eating.
“Gustatory sweating”
Autonomic neuropathy in diabetes and its effect on the heart and blood vessels
Blood pressure may drop sharply after sitting or standing, causing a person to feel light-headed/ faint.
Heart rate may stay high, instead of rising and falling in response to normal body functions and physical activity
Autonomic neuropathy and the eyes (pupil)
Autonomic neuropathy can affect the pupils of the eyes, making them less responsive to changes in light.
A person may not be able to see well when a light is turned on in a dark room or may have trouble driving at night.
Bladder and diabetes?
Bladder might not empty completely etc and other diabetic related problems. You can do an ultrasound of the bladder to double check structure and whether it empties or not etc
Where does amyotrophy usually occur?
Pelvic girdle and thigh
Kimmelsteil- Wilson Syndrome or Nodular Glomerulosclerosis??
Lol, other names for diabetic nephropathy
Consequences of diabetic nephropathy?
Development of hypertension
Relentless decline of renal failure (reduction in GFR of 1ml/min/month)
Accelerated vascular disease
Screening for nephropathy
Use urinary albumin creatinine ratio (ACR) to screen for diabetic kidney disease
Screen all patients aged 12 or over
At diagnosis & annually
May use RANDOM rather than 1st pass urine sample as initial check
Confirm abnormal result with EMU
Dipstick test at point of care
Don’t forget U&E’s (eGFR)
How often do you screen for nephropathy?
At diagnosis and annually
From which age should you screen for nephropathy?
From age 12
Why do you check U&E’s in nephropathy?
Show if kidney is filtering etc (eGFR)
Normal albumin:creatinine ratios in men and women?
<3.5mg/mol creatinine (women)
Measuring microalbumin
Microalbuminuria: 30-300mg/ml
Macroalbuminuria: >300mg/ml
How could you check for nitrites/leucocytes/blood in urine?
Mid-stream urine sample
False positives for micro-albuminuria
Vaginal discharge Pregnancy Menstruation UTI "other illnesses" on-diabetic renal disease
Which eye problems do people with diabetes develop?
Cataracts
Glaucoma (increase in fluid pressure in eye leading to increased pressure on optic nerve)
Retinopathy
Acute hyperglycemia (blurring)
How much more common is glaucoma in people with diabetes vs people without diabetes?
Glaucoma is twice as common in people with diabetes
How could you check for maculopathy?
Optical coherence tomography
Treatment for maculopathy? (/retinopathy)
Laser
Vitrectomy
Anti-VGEF injection
Causes of erectile dysfunction
Diabetes Chronic renal failure Hepatic failure Multiple Sclerosis Severe depression Other (vascular disease, low HDL, high cholesterol, hormonal deficiency) Other risk factors: Spinal cord injuries Pelvic and urogenital surgery and radiation Substance abuse Alcohol: >600ml/wk Smoking amplifies other risk factors Medications may be responsible for ~25% of cases of ED Bicycle riding
Medications which can cause erectile dysfunction
Anti-hypertensive drugs All capable Common: thiazides and beta blockers Uncommon: calcium channel blockers, alpha-adrenergic blockers, and ACE inhibitors CNS drugs: Antidepressants, tricyclics, SSRIs Tranquilizers Sedatives Analgesics
Contraindications for PDE inhibitor treatment (for erectile dysfunction)
nitrates/ nicorandil medication
Recent stroke/Myocardial infarction within 3 months.
Hypotension (BP less than 90/50mmHg).
Severe hepatic dysfunction.
Hereditary degenerative retinal disorders.
Concomitant treatment for ED (except counselling).
PDE inhibitors used to treat erectile dysfunction
Sildenafil
Tadalafil
Vardenafil
Sildenafil
Taladafil
Vardenafil are PDE inhibitors, what could they be used for?
Treatment of erectile dysfunction
Which organ filters out lactate?
Liver
