Pediatric Healthy Lifestyles & Nutrition Toolkit | Page 45

Obesity Pharmacotherapy

5. Phentermine( mean change in BMI: 4-5 %)
a.
Patient Selection:
i.
FDA-approval:
1.
BMI ≥30 kg / m 2
2.
or ≥27 kg / m 2 in presence of weight related comorbidities
3.
Other Considerations
a.
strong hunger or poor satiety
b.
low energy
4.
CONTRAINDICATIONS
a.
history of substance abuse
b.
history of CVD including arrhythmias, CAD, uncontrolled HTN
c.
hyperthyroidism
d.
glaucoma
e.
history or current use of MAOI
f.
agitated state
ii.
USE CAUTION
1.
high blood pressure( ensure adequate control of HTN before starting phentermine)
2.
history of congenital heart disease( consider cardiology consult before starting)
3.
taking SSRIs( fluoxetine / Prozac, sertraline / Zoloft, citalopram / Celexa) or SNRIs,
duloxetine / Cymbalta, venlafaxine / Effexor, mirtazapine / Remeron)
4.
renal impairment
b.
To Start Phentermine:
i.
Check for heart murmur, BP, HR, creatinine
ii.
Review warnings with patient and family: High blood pressure, Palpitations, Tachycardia, SOB,
chest pain, lower extremity edema( primary pulmonary hypertension), Agitation, Restlessness,
Insomnia, Euphoria / dysphoria, Tremor, Headache, Dry mouth, Diarrhea, Constipation
iii. Medicaid does not cover but inexpensive with a Lomaira discount card or Good Rx( e. g., $ 15-
20 / month).
c.
Start phentermine 4 mg QAM for 2 weeks
i.
Formulations: 8 mg tab( Lomaira
), 15 mg cap, 30 mg cap, 37.5 mg tab and cap
ii.
Advance to 8 mg QAM after 2 weeks.
iii. Phentermine is a controlled substance( Class IV); follow local prescribing regulations
iv. FDA approved for only“ short term use” – 12 weeks( Qsymia
is approved down to age 12 years
v.
for long term use.) Document off-label use and consent for treatment in medical record(“ We discussed that phentermine is FDA approved for‘ short term’ weight loss in youth older than 16. We reviewed the side effects of this medication, and that there are unknown side effects as well. Patient’ s parent / guardian consents to treatment.”) vi. Give family: phentermine patient info and off-label prescribing information vii. Follow-up:
1. See patient every monthly x 3 initially to review weight loss, BP, HR, exam, side effects, risks / benefits, and off-label use at each visit
2. Dosage should be individualized to obtain adequate response with lowest effective dose. If BMI is not stabilized or if patient develops tolerance, consider: 1) discontinuing phentermine, or 2) increasing dose by 4-8 mg increments( max of 15 or 16 mg daily will avoid most side effects) or 3) adding topiramate or other AOM such as GLP1RA viii. Discontinue: 1. If BMI continues to increase 2. Develops adverse side effects
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