Weight Management Flashcards
What is the BMI equation?
BMI = weight (kg) / [height x height (m)]
How many calories are there in 1g of carbohydrate, protein and fat?
Carbohydrate / protein = 4 calories
Fat = 9 calories
How does Optifast work?
12 weeks, 5:2 intermittent VLCD (very low calorie diet)
5 days of normal eating, 2 days of 800kcal/day meal replacement shakes
What are the BMIs for underweight, normal, overweight and obese? (based on Asian standards)
Underweight <18.5
Normal 18.5-22.9
Overweight: 23-27.4
Obese ≥27.5
(higher percentage of fat in Asians)
How to diagnose obesity?
BMI, waist circumference
What is a normal waist circumference and waist hip ratio for males and females?
Males: waist circumference ≤90cm or waist hip ratio ≤0.9
Females: waist circumference ≤80cm or waist hip ratio ≤0.85
What medications do people misuse for obesity?
Laxatives (induce diarrhoea)
Diuretics (induce diuresis)
Thyroxine (increase metabolic rate)
How much weight should patients lose?
Aim to lose 0.5-1kg/week
Short term goal of 5-10% weight loss over 6 months
What drugs (and class i.e. GSL) are used for obesity?
Orlistat (P-only, min age 18y)
Phentermine (POM)
Liraglutide (POM)
How does Orlistat work?
Reversible inhibitor of gastric and pancreatic lipases -> block GI fat absorption
Common side effects of Orlistat?
Abd cramps, flatulence, oily stools, faecal incontinence
Dose of Orlistat? And administration
120mg up to TDS (max 360mg/day, up to 4 years)
take before or up to 1h after meals
Should Orlistat be discontinued if treatment is not working?
Yes, stop after 12 weeks if patient cannot lose ≥5% of initial body weight
How does phentermine work?
Centrally acting appetite suppressant
Minimum age of phentermine and liraglutide?
12 years old
Dose of phentermine? and administration
Initial: 30mg OD
Maintenance: 15-30mg in one to two divided doses (give 2nd dose 10-14h before bed)
Adm: 30min-1h before breakfast, swallow whole
How long should phentermine be used for?
12 weeks, then drug-free period for 4-12 weeks (max 6-12 months)
Common side effects of phentermine?
tachycardia, palpitations, elevated BP, N/V, dry mouth, abd pain, insomnia, restlessness, nervousness
Rare side effects of phentermine?
psychotic episodes, hallucinations, euphoria
How long should liraglutide be used for?
12 weeks, stop after that if patient has not lost ≥5% of their body weight
Side effects of liraglutide?
Common: HA, N/V/D/C
Rare: pancreatitis, thyroid disease, thyroid C-cell tumour