Download The Skinny On Weight Loss Drugs

The Skinny On Weight
Loss Drugs
Siggi Ming, ARNP, NP-C
Weight Loss Center of Oklahoma
Objectives
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Learner will be able to identify
pharmacological agents currently approved
by the FDA for the treatment of obesity
Learner will be able to identify indications
for the use of pharmacological agents when
treating overweight/obese patients
Learner will be able to discuss the use of
pharmacological agents in combination with
behavior modification, nutrition, and use of
supplements in the treatment of
overweight/obesity
Definition of Overweight/Obesity
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Overweight: BMI of 25.0 – 29.9 kg/m2
Obese: BMI of 30.0 – 39.9 kg/m2
Morbidly Obese: BMI of 40.0 kg/m2
and >
When to Treat
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Any time comorbidities are present,
i.e. DM II, hyperlipidemias, heart
disease, GERD, hypertension,
metabolic syndrome, sleep apnea,
stress incontinence
Any time the patient requests help
with weight loss efforts
How Is Overweight/Obesity
Treated?
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Behavior Modification and Lifestyle
Changes
Nutritional Counseling
Exercise Counseling
Correcting Endocrine Imbalances
Supplements
Prescription Medications
Pharmacologic Agents
Orlistat
 The only FDA approved drug for long
term use
 Lipase Inhibitor; inhibits absorption of dietary fat
 Minimal systemic absorption
 Tmax approx. 8 hrs
 Half life approx. 1-2 hrs
 Metabolism occurs mainly in GI wall
 Elimination via fecal route (97%)
Orlistat Indications &
Dosage
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Obesity Management
Weight Loss
Weight maintenance
120 mg po tid with or < 1 hr after fat
containing meal
Omit if meal is non-fat
Orlistat Contraindications
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Hypersensitivity
Chronic malabsorption syndromes
Cholestasis
Hx of calcium oxalate kidney stones
Hx of Anorexia or bulimia
Hx of organ transplant
Orlistat Adverse Reactions
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Serious:
Hypersensitivity (anaphylaxis)
Angioedema
Vitamin deficiencies (fat soluble vit)
hepatotoxicity
Orlistat Adverse Reactions
Common:
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Oily spotting
Flatulence with fecal discharge
Fecal urgency and incontinence
Fatty, oily stools
Abdominal discomfort
Orlistat Drug Interactions
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Warfarin: Watch for increased INR due
to decreased Vitamin K absorption
Cyclosporine: Decreased levels
Amiodarone: Decreased levels
Fat soluble vitamins (K, A, D, E):
Decreased absorption
Thyroid hormone: Decreased
absorption
Orlistat Safety
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Pregnancy Category B
Lactation safety unknown
Monitoring: no routine testing
recommended
Drugs approved for short term use
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Phentermine
Diethylpropion
Phendimetrazine
Phentermine
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FDA approved for short term use (up
to 12 weeks)
Sympathomimetic; stimulates CNS
activity; stimulates catecholamine
release, thereby decreasing hunger
Rapidly absorbed from GI tract
Half life approx. 24 hrs
Excretion: 70-80% unchanged in urine
Phentermine Indications &
Dosage
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Short term treatment of obesity
37.5 mg po qd before 1000 to avoid
insomnia
Start with ½ strength
Increase dosage to full strength if ½
strength not causing enough appetite
suppression
Phentermine Contraindications
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Hypersensitivity
MAOI use
Arteriosclerosis
Cardiovascular disease
Hyperthyroidism
Glaucoma
Agitation
Hx of drug abuse
Pregnancy
Breastfeeding
Phentermine Adverse Reactions
Serious:
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Dependency
Psychosis
Tachycardia
Hypertension
Pulmonary hypertension
Valvular heart disease
Phentermine Adverse Reactions
Common:
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Palpitations
Tachycardia
Restlessness
Insomnia
Diarrhea
Xerostomia
Hypertension
Euphoria
Headache
Phentermine Drug Interactions
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Anorexiants/stimulants (increased risk
of CV, CNS stimulation)
MAOIs (hypertensive crisis)
Linezolid (increased risk for HTN)
Effexor (additive effect)
Phentermine Safety
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Pregnancy Category C
Lactation: possibly unsafe
CV evaluation at baseline (ECG, BP,
physical CV exam; consider echo at
baseline and after dc)
Schedule IV
Diethylpropion
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FDA approved for short term use (up
to 12 weeks)
Sympathomimetic; stimulates CNS
activity; stimulates catecholamine
release, thereby decreasing hunger
Rapidly absorbed
Half life 4-6 hrs
Excretion: urine
Diethylpropion Indications &
Dosage
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Short term treatment of obesity
25 mg po up to tid; 75 mg ER qd
25 mg approx. 1 hr before “hungriest”
time of day; may take up to tid
Do not take after 1600 to avoid
insomnia
75 mg ER q am
Diethylpropion
Contraindications
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Hypersensitivity
Pulmonary hypertension
Severe hypertension
Agitation
Valvular heart disease
Heart murmur
Cardiovascular disease
Seizure disorder
Advanced arteriosclerosis
Diethylpropion Adverse
Reactions
Serious:
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Tachycardia
Hypertension
Pulmonary hypertension
Valvular heart disease
Hallucinations
Psychosis
Leukopenia
Diethylpropion Adverse
Reactions
Common:
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Dry mouth
Diarrhea/constipation
Restlessness
Anxiety
Insomnia
Headache
Hypertension
Palpitations
Arrhythmias
Diethylpropion Drug
Interactions
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Anorexiants/stimulants (increased risk
of CV and CNS stimulation
MAOIs (hypertensive crisis)
Linezolid (increased risk of HTN)
Effexor (additive effects)
Diethylpropion Safety
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Pregnancy Category B
Lactation safety unknown
Cardiovascular evaluation at baseline;
ECG, BP, physical CV exam)
Consider echo periodically and after dc
Schedule IV
Phendimetrazine
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FDA approved for short term use (up
to 12 weeks)
Sympathomimetic; stimulates CNS
activity; stimulates catecholamine
release, thereby decreasing hunger
Rapidly absorbed
Half life 2 hrs (10 hrs ER)
Excretion: urine
Phendimetrazine
Indications & Dosage
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Short term treatment of obesity
17.5-35 mg po bid-tid; 1 hr ac
Do not give after 1600 to avoid
insomnia
105 mg ER po q am 30-60 mins ac
Phendimetrazine
Contraindications
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Hypersensitivity
Symptomatic cardiovascular disease
Moderate/severe hypertension
Hyperthyroidism
Agitation
MAOI use
Valvular heart disease
Pregnancy
Glaucoma
Advanced arteriosclerosis
Phendimetrazine Adverse
Reactions
Serious:
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Hypertension
Tachycardia
Pulmonary hypertension
Withdrawal if abrupt dc after long
term high-dose use
Phendimetrazine Adverse
Reactions
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Palpitations
Tachycardia
Restlessness
Hypertension
Insomnia
Agitation
Dizziness
Headache
Flushing
Sweating
Tolerance
Diarrhea/constipation
Common:
Phendimetrazine Drug
Interactions
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Anorexiants/stimulants (increased risk
of CV and CNS stimulation
MAOIs (hypertensive crisis)
Linezolid (increased risk of HTN)
Effexor (additive effects)
Phendimetrazine Safety
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Pregnancy Category C
Lactation possibly unsafe
Cardiovascular evaluation at baseline;
ECG, BP, physical CV exam
Consider echo periodically and after dc
Schedule III
Drugs Used Off Label
Pristiq
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Antidepressant (SNRI)
Side effects include decreased
appetite, weight loss
Seems to decrease cravings
Drugs Used Off Label
Topamax
 For migraine/headache; seizure
disorders
 Side effects include weight loss,
anorexia
 Many undesirable side effects
Drugs Used Off Label
Spironolactone
 Decreases CHO cravings
 Useful prior to menses
 Start the day premenstrual S/S begin,
stop when menstrual flow ceases
Drugs Used Off Label
Pindolol
 Weak beta blocker
 Use with phentermine, diethylpropion
to block stimulant effect without
affecting anorectic effect
hCG
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Human chorionic gonadotropin
Hormone secreted by the female body
in response to pregnancy
Used off and on since the 1950s in
conjunction with a very low calorie
diet (usually 500 kcal/day)
hCG
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No evidence that hCG is associated
with weight loss
No evidence that the use of hCG is
safe
ASBP strongly discourages the use of
hCG for weight loss
Supplements
Good quality supplements can aid
weight loss efforts by
- raising resting metabolic rate
- increasing lipid metabolism
- curbing hunger
- raising energy levels
Combined Effort
Nutrition
 Behavior
 Lifestyle
Medications/Supplements
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