Mebendazole is a drug used to treat infections caused by various nematodes (roundworms). It works by inhibiting the formation of microtubules in worms and depleting their glucose levels. Mebendazole is typically used as a single 100mg dose or twice daily doses for 3 days to treat infections like pinworm, roundworm, and hookworm. Common side effects are mild and include nausea, vomiting, and diarrhea. Mebendazole is contraindicated in pregnancy and those hypersensitive to it, and safety in young children is not established.

1. by Cindy A. Escoba &
Edilyn Mae S. Nipaya

2. What is mebendazole?
• Mebendazole is a synthetic
benzimidazole compound that
is effective against a wide
spectrum of nematodes.
• It is a drug of choice in the
treatment of infections by
whipworm, pinworm,
hookworms, and roundworm.
• Example Vermox, Antiox

4. Mebendazole is methyl 5-
benzoylbenzimidazole-2-carbamate.
Mebendazole is a white to
slightly yellow powder with a
molecular weight of 295.29.
It is less than 0.05% soluble in
water, dilute mineral acid solutions,
alcohol, ether and chloroform, but is
soluble in formic acid.

5. Composition
Mebendazoles are available in chewable tablets, each
containing 100 mg of mebendazole.
Inactive ingredients are:
• colloidal silicon dioxide
• hydrogenated vegetable oil
• magnesium stearate
• microcrystalline cellulose,
• sodium lauryl sulfate
• sodium saccharin
• sodium starch glycolate
• Talc
• tetrarome orange
• FD&C yellow No. 6.

6. II. MECHANISM OF ACTION
Mebendazole inhibits the formation of
the worms' microtubules and causes the
worms' glucose depletion.
Selectively and irreversibly inhibits uptake of
glucose and other nutrients by susceptible
helminthes.
ROUTE ONSET PEAK DURATION
Oral Unknown 2-4 hr Variable

7. III. Indication/s and Dosages
Pinworm
• - Adults and children older than age 2:
• - 100 mg P.O. (per os: orally) as a single dose; repeat if
infestation persists 2-3 weeks later.
Roundworm, whipworm, and hookworm
• - Adults and children older than age 2:
• - 100 mg P.O. b.i.d. (bis in die: twice daily) for 3 days;
repeat if infestation persists 3 weeks later.
Trichinosis
• - Adults
• - 200 to 400 mg P.O. t.i.d. (ter in die: three times a day)
for 3 days; then 400 to 500 mg t.i.d. for 10 days.

8. III. Indication/s and Dosages
Capillariasis
• - Adults and children
• - 200 mg P.O. b.i.d. (bis in die: twice daily)
for 20 days.
Dracunculiasis
• - Adults
• - 400 to 800 mg P.O. daily for 6 days.

10. Contraindicated
in patients
hypersensitive
to drug.
Safe use in
children
younger than
age 2 hasn’t
been
established.
Contraindicated
in pregnant
women
because it has
been shown to
be embryotoxic
Teratogenic in
experimental
animals.
Should be used
with caution in
patients with
cirrhosis
IV. Contraindications and Caution

11. v. Adverse effects
CNS: seizures, fever,
mild nausea, vomiting,
agranulocytosis
Skin: Rare side effects,
usually with high-dose
therapy, are hypersensitivity
reactions (rash, urticaria)
and alopecia
GIT: transient abdominal pain
and diarrhea in massive
infestation and during
expulsion of worms and
elevation of liver enzymes.

12. VI. Responsibilities
vi. responsibilities
Arrange for second course of treatment if
patient is not cured 3 weeks after treatment.
Treat all family members for pinworm
infestation.
Disinfect toilet facilities after patient use.
(pinworm)
Arrange for daily laundry of bed linens, towels,
night clothes, and undergarments. (pinworm)
Give via side drip

13. VI. Responsibilities
vi. responsibilities
Assess for pregnancy, lactation and
allergy to mebendazole.
Assess for temperature, bowel
sounds and output.
Culture for ova and parasites.
Administer drug with food; tablets may be
chewed, swallowed whole, or crushed and
missed with food.