Drugs used for Diabetes Mellitus
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Transcript Drugs used for Diabetes Mellitus
Drugs used for Diabetes
Mellitus
1
Introduction
There are 2 types of diabetes mellitus:
Type 1: Insulin-dependent diabetes mellitus
(IDDM)
Destruction
of pancreatic beta cells
Is the result of an autoimmune process
Type 2: Non-insulin dependent diabetes
mellitus (NIDDM)
Results
from a combination of insulin resistance
and altered insulin secretion
2
Characteristics of Type 1 & Type 2
Diabetes Mellitus
Age of onset
Acuteness of onset
Presenting features
Body habitus
Control of diabetes
Ketoacidosis
Insulin requirement
Control by oral agents
Control by diet alone
Complications
Type 1
Type 2
Usually < 25 years
Usually sudden
Polyuria, polydipsia,
polyphagia, acidosis
Often thin
Difficult
Frequent
Always
Never
Never
Frequent
Usually > 40 years
Usually gradual
Often asymptomatic
Usually overweight
Easy
Seldom, unless under stress
Often unnecessary
Frequent
Frequent
Frequent
3
Oral Antidiabetic Drugs
For the treatment of type 2 (non-insulindependent) diabetes mellitus
Use only after diet modification & exercise
fail to produce glycemic control
Should be used to augment the effect of
diet & exercise, not to replace them
4
Summary of treatment targets for cardiovascular risk factor
intervention in diabetic patients
Evidence-based targets for managing cardiovascular risk factors
Fasting blood glucose
</= 6mmol/l
HbA1c
< 7%
Total cholesterol
< 5mmol/l
LDL cholesterol
< 3 mmol/l
Blood pressure threshold for intervention 140/90mmHg
-Target for treatment
</= 140/80mmHg
-if significant proteinuria
</= 125/75mmHg
Recent guidelines recommend statin and low-dose aspirin treatment where the 10year coronary heart disease ridk is less than 15%
-before adding aspirin ensure blood pressure is controlled
-combination antihypertnsive treatment is necessary in the majority of patients to
achieve blood pressure targets
5
-other recommendations include HDL>1.2mmol/l and fasting
triglycerides<1.7mmol/l
Sulphonylureas
Act mainly by augmenting insulin secretion
May also increase tissue response to
insulin
Effective only when some residual
pancreatic beta-cell activity is present
Considered for patients who are not
overweight, or in whom Metformin
(Glucophage®) is contraindicated or not
tolerated
6
Sulphonylureas (Cont‘d)
Short-acting:
Tolbutamide: 0.5-1.5 g daily in divided doses, with or
immediately after breakfast; Max: 2 g daily
Gliclazide (Diamicron®): 40-160 mg daily in divided
doses, with breakfast; Max: 320 mg daily
Intermediate-acting:
Glipizide (Minidiab®): 2.5-15 mg daily in divided
doses, before breakfast; Max: 20 mg daily
7
Sulphonylureas (Cont‘d)
Long-acting:
Chlorpropamide (Diabinese®): 250 mg daily
with breakfast; Max: 500 mg
Glibenclamide (Daonil®): 5 mg daily with or
immediately after breakfast; Max: 15 mg daily
Glimepiride (Amaryl®): 1-4 mg daily shortly
before or with first main meal; Max: 4 mg daily
8
Sulphonylureas (Cont‘d)
Contraindications:
Severe hepatic and renal impairment
Breast-feeding and pregnancy
Elderly (Chlorpropamide, glibenclamide)
Adverse effects:
Nausea, vomiting, diarrhoea and constipation
Increased appetite and weight gain
Hypoglycaemia
Hypersensitivity
9
Biguanides
Decreasing gluconeogenesis in the liver
Increase peripheral utilisation of glucose by
muscle
Acts only in the presence of endogenous insulin
Metformin (Glucophage®) is the only available
biguanide
Is antihyperglycemic, not hypoglycemic
Recommended for obese or insulin resistant
diabetic patients
10
Biguanides (Cont’d)
Metformin:
500 mg bd-tid; Max: 3 g, usually limit to 2 g daily
Contraindications:
Hepatic or renal impairment (must withdraw)
Ketoacidosis
Predisposition to lactic acidosis: severe dehydration,
which is most likely to occur in patients with renal
impairment
11
Biguanides (Cont’d)
Contraindications (Cont’d):
Infection, shock, trauma, heart failure,
respiratory failure, recent myocardial
infarction, severe peripheral vascular disease
Hepatic impairment, alcohol dependency
Use of iodine-containing x-ray contrast media
(do not restart melformin until renal function
returns to normal)
Pregnancy and breast-feeding
12
Biguanides (Cont’d)
Adverse effects:
Decreased appetite
Nausea, vomiting and diarrhoea
Lactic acidosis (rarely)
Decreased absorption of vitamin B12 and folic
acid
Allergic skin reactions
13
Biguanides (Cont’d)
Nursing alerts:
Take metformin with meals and increase
dosage slowly to minimise GI adverse effects
Lactic acidosis, characterised by drowsiness,
malaise, bradycardia and hypotension is a
rare but serious adverse effect. Since this is a
medical emergency, report to the physician
immediately if suspected
14
Alpha glucosidase inhibitor
Delay the digestion & absorption of starch
& sucrose by inhibition of intestinal alpha
glucosidase in the intestine
Acarbose (Glucobay®)
50-100 mg tid; Max: 200 mg tid
15
Alpha glucosidase inhibitor
(Cont’d)
Contraindications:
Pregnancy and breast-feeding
Inflammatory or malabsorptive intestinal
disorders
Hepatic impairment
Severe renal impairment
16
Alpha glucosidase inhibitor (Cont’d)
Adverse effects:
Flatulence, soft stools, diarrhoea, abdominal
distention and pain
Liver dysfunction
17
Alpha glucosidase inhibitor (Cont’d)
Nursing alerts
Tablets should be taken with first mouthful of
food
Absorption of sugar (sucrose) is blocked by
acarbose. When hypogylcaemia occurs, only
glucose should be given
18
Metglitinides
Stimulate insulin release
Rapid onset of action & short duration
Taken shortly before meals
19
Metglitinides (Cont’d)
Repaglinide (NovoNorm®):
500 mcg – 4 mg daily within 30 min before
main meals; Max: 16 mg daily
Nateglinide:
60 mg tid within 30 min before main meals;
Max: 180 mg tid
20
Metglitinides (Cont’d)
Contraindications:
Ketoacidosis
Pregnancy and breast-feeding
Severe hepatic impairment (for repaglinide)
21
Metglitinides (Cont’d)
Adverse effects:
Hypoglycaemia
Hypersensitivity reactions including pruritus,
rashes and urticaria
Abdominal pain, diarrhoea, constipation,
nausea and vomiting (repaglinide)
Nursing alert:
Administration must always be associated
with meals
22
Thiazolidinediones
Also known as Glitazones
Reduce peripheral insulin resistance by
enhancing uptake of glucose by skeletal muscle
cells
Rosiglitazone (Avandia®):
4 mg daily in combination with metformin or a
sulphonylurea; Max: 8 mg daily when with metformin
Pioglitazone (Actos®):
15-30 mg daily
23
Thiazolidinediones (Cont’d)
Contraindications:
Hepatic impairment
History of heart failure, combination of insulin
Pregnancy and breast-feeding
24
Thiazolidinediones (Cont’d)
Adverse effects:
GI disturbances, headache, anaemia
Weight gain
Oedema
Hypoglycaemia (less common for
Pioglitazone)
Liver dysfunctions (rare)
25
Thiazolidinediones (Cont’d)
Nursing Alerts:
Monitor liver function before treatment, then
every 2 months for 1 year and periodically
thereafter
Seek immediate medical attention if symptoms
such as nausea, vomiting, abdominal pain,
fatigue & dark urine develop
Discontinue if jaundice occurs
Monitor closely for oedema & other signs of
congestive heart failure
26
Non-oral antidiabetic drugs
Insulin:
Supplement the insulin secreted by pancreas
Promote uptake of glucose in muscle
Facilitate conversion of glucose to glycogen in
liver, inhibit gluconeogenesis & glycogenolysis
in liver
27
Actions of Insulin
Glucose transport into muscle & fat cells.
Increased glycogen synthesis.
Inhibition of gluconeogenesis.
Inhibition of lipolysis & increased formation
of triglycerides.
Stimulation of membrane-bound energydependent ion transporters (e.g. Na/K
ATPase).
Stimulation of cell growth
28
Insulin (Cont’d)
They are divided into short, intermediate &
long-acting preparations:
Short-acting:
Neutral/soluble insulin
E.g. Actrapid®HM,
Insulin Lispro
E.g.
Humulin R®
Humalog®
Insulin Aspart
E.g.
NovoRapid®
29
Insulin (Cont’d)
Intermediate-acting:
Isophane insulin
E.g.
Protaphane®HM, Humulin N®
Insulin zinc suspension
E.g.
Monotard®, Humulin L®
30
Insulin (Cont’d)
Long-acting:
Crystalline insulin zinc
E.g.
Ultratard®HM
Insulin glargine
E.g.
Lantus®
31
Insulin (Cont’d)
Mixed Insulins:
Biphasic isophane insulin
30%
E.g. Mixtard ®30, Humulin ®70/30
20%
soluble insulin/70% isophane insulin
soluble insulin/80% isophane insulin
E.g. Mixtard ®20
32
Insulin (Cont’d)
Dose:
Given through subcutaneous injection
According to the requirements
Short-acting:
Usually
inject 15-30 min before meals
Intermediate- & long-acting:
Once
or twice daily
Can be given in conjunction with short-acting insulin
33
Insulin Formulations
Duration of action Examples
Peak effect (h)
Duration of action (h)
Short
Insulin Injection
(soluble insulin)
2h-4h
6h-12h
Intermediate
Isophane insulin
Insulin zinc suspension
(amorphous)
5h-12h
3h-6h
12h-24h
12h-16h
Long
Insulin zinc suspension
(crystalline)
5h-14h
24h-30h
Mixed
Variable portions of
soluble & isophane
insulins
2h-10h
3h-8h
18h-20h
16h-24h
34
Insulin (Cont’d)
Precautions:
may decrease requirements in renal or
hepatic impairment, some endocrine
disorders, coeliac disease
35
Insulin (Cont’d)
Nursing Alerts:
Teach patients how to prepare & use the
subcutaneous (SC) injection, and the usual
areas used for SC injection including
abdomen, thigh & upper arm
Rotate the injection site within the general
area employed. Allow about 1 inch between
sites
36
Insulin (Cont’d)
Nursing Alerts (Cont’d):
Storage
Penfill
Cartridges not in use should be stored between 2-8 ℃
Cartridges used in the pen or carried as spare can be
used for up to one month
Vial
Vials not in use should be stored between 2-8 ℃
Vial in use can be kept at room temp for 6 weeks (Novo
Nordisk)
Vials in use can be kept at room temp for 28 days (Lilly)
37
Hypoglycaemia
Nursing Alerts:
Observe for and teach the patient about signs
and symptoms of hypoglycaemia
Tachycardia,
palpitations
Sweating
Nervousness,
headache, confusion, drowsiness
Fatigue
Rapid treatment is required
Patient
is conscious: oral glucose should be given
Patient is unconscious: IV glucose should be used
38
39
Drugs that affect the
gastrointestinal system
40
Introduction
Drugs used in gastrointestinal system or
digestive disorder primarily exert their
action by altering GI
Secretion
Absorption
Motility
They may act systemically or locally in the
GI tract
41
Physiologic and pathologic (i.e. inflammatory) prostaglandins
Cell activated by
physical, chemical,
or hormone stimuli
Traditional NSAIDs
Block COX-1 and
COX-2 enzymes
Arachidonic acid
COX-2inhibitor NSAIDs
Block COX-2 enzyme
Cyclooxygenase-1 (COX-1)
Cyclooxygenase-2 (COX-2)
Physiologic prostaglandins
Pathologic prostaglandins
•GI protection (↓gastric acid,↑mucus
production, maintain blood flow to mucosa)
•Renal protection (help maintain blood flow
and function)
•Regulate smooth muscle tone in blood
vessels (e.g., vasodilation) and lungs
(e.g., bronchodilation)
•Regulate blood clotting
•Inflammation
Vasodilation,
↑Capillary permeability
•Edema
Pain
•Leukocytosis
•Activatye white blood cells to
release inflammatory cytokines
42
Antacids & Simethicone
Antacids
Drugs that neutralize or reduce the acidity of
stomach & duodenal contents by combining
with HCl & producing salt & water
Relieve symptoms in dyspepsia, gastrooesophageal reflux disease (GERD), peptic
ulcers
Simethicone
Added to antacids as an antifoaming agent to
relieve flatulence
43
Antacids & Simethicone (Cont’d)
Antacids
Aluminium Hydroxide (500mg tablet
/6% suspension)
1-2
tablets chewed qid
Magnesium trisilicate (Mixture)
5% BP Mixture: 10ml tid po
44
Antacids & Simethicone (Cont’d)
Antacids combination products:
Triact tablet
Al(OH)3
Dried Gel 200 mg & Mg(OH)2 150 mg &
Simethicone 25 mg
Chew 1-2 tab q4-6h
Gastrocaine suspension
Oxethazaine
10mg, Al(OH)3 Dried Gel 300mg,
Mg(OH)2 100mg in 5 ml
Alumag suspension
Al(OH)3
& Mg Trisilicate
45
Antacids & Simethicone (Cont’d)
Antacids combination products (Cont’d):
Gelusil
tablet
Mg Trisilicate+ Dried Aluminium Hydroxide gel
Mylanta
tablet / suspension
CaCO3 & Mg(OH)2
Simethicone
Dimethylpolysiloxane (Gasteel® 40 mg tablet)
46
Antispasmodics
Relax smooth muscle
Relieve GI smooth muscle
spasm
Include antimuscarinics &
others
47
Antispasmodics (Cont’d)
Antimuscarinics:
Hyoscine Butylbromide (Buscopan®)
Adult:
20 mg qid po;
Child: 10 mg tid po
Propantheline bromide
15
mg tid at least 1 hr before meals & 30 mg at
night; Max: 120 mg daily
Not recommended for children
48
Antispasmodics (Cont’d)
Side effects:
Constipation
Urinary urgency and retention
Dry mouth
Transient bradycardia
49
Antispasmodics (Cont’d)
Others:
Mebeverine HCl (Duspatalin®)
Adult
& child over 10 years: 135-150 mg tid
preferably 20 min before meals
Peppermint oil (0.2 ml capsule)
1-2
capsules tid
Not recommended for children under 15 years
50
Motility stimulants
Dopamine antagonists
Stimulate gastric emptying & small
intestinal transit
Enhance strength of oesophageal
sphincter contraction
Sometimes used in non-ulcer
dyspepsia
Useful in non-specific & in cytotoxicinduced nausea & vomiting (N&V)
51
Motility stimulants (Cont’d)
Domperidone (Motilium®)
N&V:
adult:
10-20 mg q4-8h
Child: 200-400 mcg/kg q4-8h
Functional dyspepsia
10-20
mg tid before food & 10-20 mg at night
Not recommended for children
52
Motility stimulants (Cont’d)
Metoclopramide (Maxolon®)
Adult: 10 mg tid
15-19 yrs under 60 kg: 5 mg tid
1-14 yrs: 1 mg bd to 5 mg tid depend on age
Diagnostic procedures:
Adult:
10-20 mg five to ten min before exam
Child: 1-5 mg depends on age
53
Motility stimulants (Cont’d)
Side effects:
May
raised prolactin concentration
Rashes & other allergic reactions
Acute dystonic
reaction reported
Extrapyramidal effects
(Metoclopramide more prominent)
54
Motility stimulants (Cont’d)
Nursing Alert:
For patients under 20 yrs
Metoclopramide
should be used restricted to
severe intractable vomiting of known cause,
vomiting of radiotherapy & cytotoxics, aid to
GI intubation, pre-medication
Dose based on basis of body-weight
55
Ulcer-healing drugs
Peptic ulceration commonly involves the
stomach, duodenum & lower oesophagus
Due to imbalance between cell-destructive
& cell-protective effects
Helicobacter pylori & NSAIDs can weaken
the defences
Relapse is common when treatment
ceases
56
Ulcer-healing drugs (Cont’d)
Include several groups of drugs
H2-receptor antagonists
Chelates & complexes
Prostaglandin analogues
Proton pump inhibitors
57
H2-receptor antagonists
Histamine acts on receptors located on
parietal cells to increase production of HCl
Block histamine H2-receptors
Heal gastric & duodenal ulcers by
reducing gastric acid output
Relieve gastro-oesophageal reflux disease
May occasionally be used for patients with
frequent severe recurrences & for the
elderly who suffer ulcer complications
58
H2-receptor antagonists (Cont’d)
Cimetidine
Famotidine
20-40 mg bd
Not recommended for children
Nizatidine
Adult: 400 mg bd; Max: 2.4 g daily (rarely)
Child: 20-30 mg/kg daily in divided dose
150-300 mg bd
Not recommended for children
Ranitidine
Adult: 150 mg bd
Child: 2-4 mg/kg bd; Max: 300 mg daily
59
H2-receptor antagonists (Cont’d)
Side effects:
Diarrhoea & other GI
disturbances
Altered liver function tests
Headache, dizziness, rash
60
H2-receptor antagonists (Cont’d)
Nursing Alerts:
Cimetidine is a CYP450 inhibitor, avoid in
patients on warfarin, phenytoin & theophylline
Patients may experience dizziness or
drowsiness during early therapy, especially in
the elderly. Assistance may be required for
ambulatory activities
61
Chelates & complexes
Sucralfate
Complex of AL(OH)3 & sulphated sucrose
Minimal antacid properties
Protect the mucosa from acid-pepsin attack in
gastric & duodenal ulcers
2 g bd or 1 g qid 1 hr before meals & at
bedtime; Max: 8 g daily
Not recommended for children
62
Chelates & complexes
Side effects:
Constipation, diarrhoea, gastric
discomfort
Dry mouth
Headache, nausea
Hypersensitivity reactions
63
Prostaglandin analogues
Misoprostol
Synthetic prostaglandin analogue
(Prostaglandin E)
Antisecretory & protective properties
Inhibit
gastric acid secretion
Increase mucus & bicarbonate secretion
Promote healing of gastric & duodenal
ulcers
64
Prostaglandin analogues (Cont’d)
Dose:
800 mcg daily in 2-4 divided doses
For prophylaxis of NSAID-induced
gastric & duodenal ulcer
200 mcg 2-4 times daily
Not recommended for children
65
Prostaglandin analogues (Cont’d)
Side effects:
Diarrhoea (may require withdrawal)
Abdominal pain, dyspepsia, flatulence,
nausea & vomiting
Abnormal vaginal bleeding
Nursing Alerts:
Incidence of diarrhoea may be lessened
by taking dose right after meals
66
Prostaglandin analogues (Cont’d)
Nursing Alerts (Cont’d):
Manufacturer advises not to be used in
women of child-bearing age unless the pateint
requires NASID therapy & is at high risk of
complications from NSAID-induced ulceration
Patients should take effective contraceptive
measures & be advised the risks of taking
misoprostol if pregnant
67
Proton pump inhibitors
Inhibit gastric acid by irreversibly blocking the
hydrogen-potassium adenosine
triphosphatase enzyme system (“proton
pump”) of gastric parietal cell
Indicated for gastric & duodenal ulcers &
gastro-oesophageal reflux disease
Suppress gastric acid more strongly & for a
longer time than H2-receptor antagonists
68
Proton pump inhibitors (Cont’d)
Omeprazole
Esomeprazole
15-30 mg daily
Not recommended for children
Pantoprazole
20-40 mg daily
Not recommended for children
Lansoprazole
Adult: 10-40 mg daily
Child over 2 yrs: 0.7-1.4 mg/kg daily; Max: 40 mg daily
IV injection or infusion is not recommended for children
20-40 mg daily
Not recommended for children
Rabeprazole
10-20 mg daily
Not recommended for children
69
Proton pump inhibitors (Cont’d)
Side effects:
GI disturbances
Headache
Hypersensitivity reactions
70
71
Unawareness of drug’s brand name
Patient has a documented allergy to Zyloric®
Allopurinol was prescribed to this patient
The doctor prescribing was not aware that Zyloric® was
the brand name for Allopurinol
72
Tips
Check out the contents of the preparation if brand name
is used before prescribing, dispensing or administration
73
74
Improper Drug Abbreviation
IV Mitoxantrone was prescribed
The abbreviation ‘MTX’ was put on the label
An injection of Methotrexate was prepared
instead according to the abbreviation on the
label
Methotrexate was administered to the patient as
a result
75
Tips
Write drug name in full
Do not use unauthorised abbreviations
Cross check the dose & name of the drug before
preparation & administration
76
Repeated Pethidine Injection
Patient was given a Pethidine injection at A&E via a verbal
order
Nurse forgot to record this order in MAR
Prescribing Dr had not confirmed the verbal order in the
prescription
A second dose of Pethidine was administered in the ward
Patient collapsed as a result of overdose of Pethidine
77
Tips
Pethidine is a Dangerous Drug & should not be ordered
through verbal orders
For other non-DD, give a verbal order only in emergency
& exceptional circumstances
Record the verbal instruction in the MAR immediately as
‘verbal order’
After writing down the instruction, read back the details
to the Dr for double checking
78
Self-medication of Paracetamol
Patient was transferred from medical ward to ICU with
high plasma level of Paracetamol
Patient was treated with N-acetylcysteine infusion as an
antidote
Patient later admitted that she had taken approximately
15 tabs of Paracetamol (private medications) in the
medical ward to relieve her leg pain
79
Tips
Put patients’ brought-in medicines into safe custody
Do not administer the patient’s own medicines in hospital
unless they have been positively identified, specifically
prescribed & when supplies are not immediately
available inside the hospitals
80
Glibenclamide or Citalopram
An in-patient presented with severe hypotension &
vomiting
A review of the MAR revealed that Daonil®
(Glibenclamide) was written right above the prescription
for Citalopram in pencil
Upon investigation, it was discovered that some nursing
staff gave Citalopram to the patient whilst others gave
Glibenclamide
81
Tips
Familiarise with the medication &/or the patient
If there is uncertainty or confusion about a particular
prescription, always consult with the prescriber
Adequate communication between staff is the key to
preventing errors
82
Wrong Drug Name
Martindale 1 drop tds both eyes was prescribed
Martindale is the name of the drug company that
makes the eye drops
83
Tips
Prescribe in generic rather than trade name as trade
names don’t usually give indications of their constituents
84
Inappropriate Drug Dosage
A 10 month old baby was prescribed Cotrimoxazole
suspension 20mg bd
Cotrimoxazole is a combination product containing
Sulphamethoxazole 200mg & Trimethoprim 40mg per
5ml
240mg per 5 ml & 20mg = 0.42ml
It was later clarified that the dose 20mg refers to the
Trimethoprim component
Thus 120mg cotrimoxazole should have been prescribed
85
Tips
Should clearly specify drug dosage especially for
combination product
Clarify with prescriber if in doubt
86