Siggi Ming, ARNP, NP-C
Weight Loss Center of Oklahoma

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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 >

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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

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Behavior Modification and Lifestyle
Changes
Nutritional Counseling
Exercise Counseling
Correcting Endocrine Imbalances
Supplements
Prescription Medications

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%)

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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

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Hypersensitivity
Chronic malabsorption syndromes
Cholestasis
Hx of calcium oxalate kidney stones
Hx of Anorexia or bulimia
Hx of organ transplant

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Serious:
Hypersensitivity (anaphylaxis)
Angioedema
Vitamin deficiencies (fat soluble vit) hepatotoxicity

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Common:
Oily spotting
Flatulence with fecal discharge
Fecal urgency and incontinence
Fatty, oily stools
Abdominal discomfort

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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

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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
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Diethylpropion
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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 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
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Serious:
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)

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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

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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

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Hypersensitivity
Pulmonary hypertension
Severe hypertension
Agitation
Valvular heart disease
Heart murmur
Cardiovascular disease
Seizure disorder
Advanced arteriosclerosis

Diethylpropion Adverse
Reactions
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Serious:
Tachycardia
Hypertension
Pulmonary hypertension
Valvular heart disease
Hallucinations
Psychosis
Leukopenia

Diethylpropion Adverse
Reactions
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Common:
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)

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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

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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

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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

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Hypersensitivity
Symptomatic cardiovascular disease
Moderate/severe hypertension
Hyperthyroidism
Agitation
MAOI use
Valvular heart disease
Pregnancy
Glaucoma
Advanced arteriosclerosis

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Serious:
Hypertension
Tachycardia
Pulmonary hypertension
Withdrawal if abrupt dc after long term high-dose use

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Common:
Palpitations
Tachycardia
Restlessness
Hypertension
Insomnia
Agitation
Dizziness
Headache
Flushing
Sweating
Tolerance
Diarrhea/constipation

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Anorexiants/stimulants (increased risk of CV and CNS stimulation
MAOIs (hypertensive crisis)
Linezolid (increased risk of HTN)
Effexor (additive effects)

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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

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Pristiq
Antidepressant (SNRI)
Side effects include decreased appetite, weight loss
Seems to decrease cravings

Topamax
 For migraine/headache; seizure disorders
 Side effects include weight loss, anorexia
 Many undesirable side effects

Spironolactone
 Decreases CHO cravings
 Useful prior to menses
 Start the day premenstrual S/S begin, stop when menstrual flow ceases

Pindolol
 Weak beta blocker
 Use with phentermine, diethylpropion to block stimulant effect without affecting anorectic effect

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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)

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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

Good quality supplements can aid weight loss efforts by
- raising resting metabolic rate
- increasing lipid metabolism
- curbing hunger
- raising energy levels

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Nutrition
Behavior
Lifestyle
Medications/Supplements