Phentermine comes in tablets and extended-release
capsules. It usually is taken as a single daily dose in the
morning or three times a day 30 minutes before meals. Follow
the directions on your prescription label carefully, and ask
your doctor or pharmacist to explain any part you do not understand.
Take phentermine exactly as directed.
Most people take the drug for 3-6 weeks; the
length of treatment depends on how you respond to the medication.
Phentermine can be habit-forming. Do not take a larger dose,
take it more often, or for a longer period than your doctor
tells you to.
To prevent side effects, phentermine should
be taken with meals. If you are taking an extended-release (long-acting)
product, do not chew or crush the tablet. There are some tablets
that can be crushed and mixed with food.
What special precautions should I follow? Return
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Before taking phentermine,
tell your doctor and pharmacist if you are allergic to phentermine
or any other drugs.
tell your doctor and pharmacist what prescription and nonprescription
medications you are taking, especially fluoxetine (Prozac),
fluvoxamine (Luvox), guanethidine, insulin, MAO inhibitors
[phenelzine (Nardil) and tranylcypromine (Parnate)] even if
you stopped taking them within the past 2 weeks, medications
for weight loss and depression, paroxetine (Paxil), sertraline
(Zoloft),and vitamins.
tell your doctor if you have or have ever had heart disease,
high blood pressure, arteriosclerosis (narrowing of the arteries),
hyperthyroidism (overactive thyroid gland), diabetes, glaucoma,
or a history of drug abuse.
tell your doctor if you are pregnant, plan to become pregnant,
or are breast-feeding. If you become pregnant while taking
phentermine, call your doctor.
you should know that this drug may make you drowsy. Do not
drive a car or operate machinery until you know how this drug
affects you.
remember that alcohol can add to the drowsiness caused by
this drug.
if you have diabetes, you may need a larger dose of insulin
while taking phentermine. Call your doctor if you have questions
or problems.
What special dietary instructions should I follow?
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Follow the diet and exercise program your
doctor has given you. Phentermine works best in combination
with a diet program.
Take the missed dose as soon as you remember
it. However, if it is almost time for the next dose, skip the
missed dose and continue your regular dosing schedule. Do not
take a double dose to make up for a missed one.
What side effects can this medication cause? Return
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Although side effects from phentermine are
not common, they can occur. Tell your doctor if any of these
symptoms are severe or do not go away:
dry mouth
unpleasant taste
diarrhea
constipation
vomiting
If you experience any of the following symptoms,
call your doctor immediately:
increased blood pressure
heart palpitations
restlessness
dizziness
tremor
insomnia
shortness of breath
chest pain
dizziness
swelling of the legs and ankles
difficulty doing exercise that you have been able to do
What storage conditions are needed for this medicine? Return
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Keep this medication in the container it came
in, tightly closed, and out of reach of children. Store it at
room temperature and away from excess heat and moisture (not
in the bathroom). Throw away any medication that is outdated
or no longer needed. Talk to your pharmacist about the proper
disposal of your medication.
In case of overdose, call your local poison
control center at 1-800-222-1222. If the victim has collapsed
or is not breathing, call local emergency services at 911.
