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Active substance(s): EFAVIRENZ

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Efavirenz 600 mg
Read all of this leaflet carefully before you start
taking this medicine because it contains important
information for you.
• Keep this leaflet. You may need to read it again
• If you have any further questions, ask your doctor,
pharmacist or nurse.
• This medicine has been prescribed for you only. Do
not pass it on to others. It may harm them, even if their
signs of illness are the same as yours
• If you get any side effects talk to your doctor or
pharmacist. This includes any possible side effects not
listed in this leaflet.
What is in this leaflet:
1. What Efavirenz is and what it is used for
2. What you need to know before you take Efavirenz
3. How to take Efavirenz
4. Possible side effects
5. How to store Efavirenz
6. Contents of the pack and other information
1. What Efavirenz is and what it is used for
Efavirenz belongs to a class of antiretroviral medicines
called non-nucleoside reverse transcriptase inhibitors
(NNRTIs). It is an antiretroviral medicine that fights human
immunodeficiency virus (HIV) infection by reducing the
amount of the virus in blood.
Your doctor has prescribed Efavirenz for you because you
have HIV infection. Efavirenz taken in combination with
other antiretroviral medicines reduces the amount of the
virus in the blood.
take Efavirenz
Do not take Efavirenz
• if you are allergic to efavirenz or any of the other
ingredients of Efavirenz listed in section 6. Contact your
doctor or pharmacist for advice.
• if you have severe liver disease.
• if you are currently taking any of the following medicines:
* astemizole or terfenadine (used to treat allergy symptoms)
* bepridil (used to treat heart disease)
* cisapride (used to treat heartburn)
* ergot alkaloids (for example, ergotamine,
dihydroergotamine, ergonovine, and
methylergonovine) (used to treat migraine and
cluster headaches)
* midazolam or triazolam (used to help you sleep)
* pimozide (used to treat certain mental conditions)
* St. John's wort (Hypericum perforatum) (a herbal
remedy used for depression and anxiety)
If you are taking any of these medicines, tell your doctor
immediately. Taking these medicines with Efavirenz could
create the potential for serious and/or life-threatening
side-effects or stop Efavirenz from working properly.
Warnings and precautions
Talk to your doctor before taking Efavirenz
• Efavirenz must be taken with other medicines that act
against the HIV virus. If Efavirenz is started because your
current treatment has not prevented the virus from
multiplying, another medicine you have not taken before
must be started at the same time.
• You can still pass on HIV when taking this medicine, so
it is important to take precautions to avoid infecting
other people through sexual contact or blood transfer.
This medicine is not a cure for HIV infection and you
may continue to develop infections or other illnesses
associated with HIV disease.
• You must remain under the care of your doctor while
taking Efavirenz.
Tell your doctor:
• if you have a history of mental illness, including
depression, or of substance or alcohol abuse. Tell your
doctor immediately if you feel depressed, have suicidal
thoughts or have strange thoughts (see section 4,
Possible side effects).
• if you have a history of convulsions (fits or seizures) or if
you are being treated with anticonvulsant therapy such as
carbamazepine, phenobarbital and phenytoin. If you are
taking any of these medicines, your doctor may need to
check the level of anticonvulsant medicine in your blood
to ensure that it is not affected while taking Efavirenz.
Your doctor may give you a different anticonvulsant.
• if you have a history of liver disease, including active
chronic hepatitis. Patients with chronic hepatitis B or C
and treated with combination antiretroviral agents have
a higher risk for severe and potentially life-threatening
liver problems. Your doctor may conduct blood tests
in order to check how well your liver is working or may
switch you to another medicine. If you have severe liver
disease, do not take Efavirenz (see section 2, 'Do not
take Efavirenz').
Once you start taking Efavirenz, look out for:
• signs of dizziness, difficulty sleeping, drowsiness,
difficulty concentrating or abnormal dreaming. These
side effects may start in the first 1 or 2 days of treatment
and usually go away after the first 2 to 4 weeks.
• any signs of skin rash. If you see any signs of a severe
rash with blistering or fever, stop taking Efavirenz and
tell your doctor at once. If you had a rash while taking
another NNRTI, you may be at a higher risk of getting a
rash with Efavirenz.
• any signs of inflammation or infection. In some patients
with advanced HIV infection (AIDS) and a history
of opportunistic infection, signs and symptoms of
inflammation from previous infections may occur soon
after anti-HIV treatment is started. It is believed that
these symptoms are due to an improvement in the
body's immune response, enabling the body to fight
infections that may have been present with no obvious
symptoms. If you notice any symptoms of infection,
please tell your doctor immediately. In addition to
the opportunistic infections, autoimmune disorders (a
condition that occurs when the immune system attacks
healthy body tissue) may also occur after you start
taking medicines for the treatment of your HIV infection.
Autoimmune disorders may occur many months after
the start of treatment. If you notice any symptoms of
infection or other symptoms such as muscle weakness,
weakness beginning in the hands and feet and moving
up towards the trunk of the body, palpitations, tremor or
hyperactivity, please inform your doctor immediately to
seek necessary treatment.

• changes in body fat. Redistribution, accumulation or loss
of body fat may occur in patients receiving combination
antiretroviral therapy. Tell your doctor if you notice
changes in your body fat.
• bone problems. Some patients taking combination
antiretroviral therapy may develop a bone disease
called osteonecrosis (death of bone tissue caused
by loss of blood supply to the bone). The length of
combination antiretroviral therapy, corticosteroid use,
alcohol consumption, severe immunosuppression,
higher body mass index, among others, may be some of
the many risk factors for developing this disease. Signs
of osteonecrosis are joint stiffness, aches and pains
(especially of the hip, knee and shoulder) and difficulty in
movement. If you notice any of these symptoms please
inform your doctor.
Children and adolescents
Efavirenz is not suitable for children weighing less than
40 kg. Other efavirenz formulations are available in the
market for these patients.
Other medicines and Efavirenz
You must not take Efavirenz with certain medicines.
These are listed under 'Do not take Efavirenz', at the start
of section 2. They include some common medicines and
a herbal remedy (St. John's wort) which can cause
serious interactions.
Tell your doctor, pharmacist or nurse if you are taking,
have recently taken or might take any other medicines.
Efavirenz may interact with other medicines, including
herbal medicine such as Ginkgo biloba extracts. As a
result, the amounts of efavirenz or other medicines in your
blood may be affected. This may stop the medicines from
working properly, or may make any side effects worse. In
some cases, your doctor may need to adjust your dose or
check your blood levels. It is important to tell your doctor
or your pharmacist if you are taking any of the following:
• Other medicines used for HIV infection:
* protease inhibitors: darunavir, indinavir, lopinavir/
ritonavir, ritonavir, ritonavir boosted atazanavir,
saquinavir or fosamprenavir/saquinavir. Your doctor
may consider giving you an alternative medicine or
changing the dose of the protease inhibitors.
* maraviroc
* a combination medicine containing efavirenz,
emtricitabine and tenofovir, which is currently known
as Atripla. Efavirenz should not be taken with Atripla
since it contains efavirenz, the active ingredient
of Efavirenz.
• Medicines used to treat infection with the hepatitis C
virus: boceprevir, telaprevir.
• Medicines used to treat bacterial infections, including
tuberculosis and AIDS-related mycobacterium avium
complex: clarithromycin, rifabutin, rifampicin. Your
doctor may consider changing your dose or giving you
an alternative antibiotic. In addition, your doctor may
prescribe a higher dose of Efavirenz.
• Medicines used to treat fungal infections (antifungal):
* voriconazole. Efavirenz may reduce the amount of
voriconazole in your blood and voriconazole may
increase the amount of efavirenz in your blood. If
you take these two medicines together, the dose
of voriconazole must be increased and the dose of
efavirenz must be reduced. You must check with your
doctor first.
* itraconazole. Efavirenz may reduce the amount of
itraconazole in your blood.
* posaconazole. Efavirenz may reduce the amount of
posaconazole in your blood.
• Medicines used to treat malaria: atovaquone/proguanil:
Efavirenz may reduce the amount of atovaquone/
proguanil in your blood.
• Medicines used to treat convulsions/seizures
(anticonvulsants): carbamazepine, phenytoin,
phenobarbital. Efavirenz can reduce or increase the
amount of anticonvulsant in your blood. Carbamazepine
may make Efavirenz less likely to work. Your doctor may
need to consider giving you a different anticonvulsant.
• Medicines used to lower blood fats (also called statins):
atorvastatin, pravastatin, simvastatin. Efavirenz can
reduce the amount of statins in your blood. Your doctor
will check your cholesterol levels and will consider
changing the dose of your statin, if needed.
• Methadone (a medicine used to treat opiate addiction):
your doctor may need to change your dose of methadone.
• Sertraline (a medicine used to treat depression): your
doctor may need to change your dose of sertraline.
• Bupropion (a medicine used to treat depression or
to help you stop smoking): your doctor may need to
change your dose of bupropion.
• Diltiazem or similar medicines (called calcium channel
blockers): when you start taking Efavirenz, your doctor
may need to adjust your dose of the calcium
channel blocker.
• Immunosuppressants such as cyclosporine, sirolimus, or
tacrolimus (medicines used to prevent organ transplant
rejection): when you start or stop taking Efavirenz, your
doctor will closely monitor your plasma levels of the
immunosuppressant and may need to adjust its dose.
• Hormonal contraceptive, such as birth control pills, an
injected contraceptive (for example, Depo-Provera), or
a contraceptive implant (for example, Implanon): you
must also use a reliable barrier method of contraception
(see 'Pregnancy, breast-feeding and fertility'). Efavirenz
may make hormonal contraceptives less likely to work.
Pregnancies have occurred in women taking Efavirenz
while using a contraceptive implant, although it has not
been established that the Efavirenz therapy caused the
contraceptive to fail.
• Warfarin or acenocoumarol (medicines used to reduce
clotting of the blood): your doctor may need to adjust
your dose of warfarin or acenocoumarol.
• Ginkgo biloba extracts (a herbal remedy)
Taking Efavirenz with food and drink
Taking Efavirenz on an empty stomach, may reduce the
undesirable effects (see section 3 'How to take Efavirenz').
Pregnancy, breast-feeding and fertility
Women should not get pregnant during treatment with
Efavirenz and for 12 weeks thereafter.
Your doctor may require you to take a pregnancy test to
ensure you are not pregnant before starting treatment
with Efavirenz.
If you could get pregnant while receiving Efavirenz, you
need to use a reliable form of barrier contraception (for
example, a condom) with other methods of contraception
including oral (pill) or other hormonal contraceptives (for
example, implants, injection). Efavirenz may remain in
your blood for a time after therapy is stopped. Therefore,
you should continue to use contraceptive measures, as
above, for 12 weeks after you stop taking Efavirenz.

Tell your doctor immediately if you are pregnant or intend
to become pregnant. If you are pregnant, you should take
Efavirenz only if you and your doctor decide it is clearly
needed. Ask your doctor or pharmacist for advice before
taking any medicine.
Serious birth defects have been seen in unborn animals
and in the babies of women treated with efavirenz during
pregnancy. If you have taken efavirenz during your
pregnancy, your doctor may request regular blood tests
and other diagnostic tests to monitor the development of
your child.
You should not breast-feed your baby if you are
taking Efavirenz.
Driving and using machines
Efavirenz may cause dizziness, impaired concentration,
and drowsiness. If you are affected, do not drive and do
not use any tools or machines.
Efavirenz contains lactose
Each Efavirenz 600mg Film-coated tablet contains 128 mg
of lactose monohydrate.
If you have been told by your doctor that you have an
intolerance to some sugars, contact your doctor before
taking this medicine.
3. How to take Efavirenz
Always take this medicine exactly as your doctor or
pharmacist has told you. It is recommended that the tablet
be swallowed whole with water. Check with your doctor
or pharmacist if you are not sure. Your doctor will give you
instructions for proper dosing.
• Efavirenz is for oral use. Efavirenz is recommended to
be taken on an empty stomach preferably at bedtime.
This may make some side effects (for example, dizziness,
drowsiness) less troublesome. An empty stomach is
commonly defined as 1 hour before or 2 hours after
a meal.
• The dose for adults is 600 mg once daily. However, if
administered together with rifampicin, other efavirenz
formulations may be used to give a total dose of 800mg.
• The dose for Efavirenz may need to be increased or
decreased if you are also taking certain medicines (see
'Other medicines and Efavirenz').
• Efavirenz must be taken every day.
• Efavirenz should never be used alone to treat HIV.
Efavirenz must always be taken in combination with
other anti-HIV medicines.

Uncommon (affects 1 to 10 users in 1,000)
• nervousness, forgetfulness, confusion, fitting (seizures),
abnormal thoughts
• blurred vision
• a feeling of spinning or tilting (vertigo)
• pain in the abdomen (stomach) caused by inflammation
of the pancreas
• allergic reaction (hypersensitivity) that may cause
severe skin reactions (erythema multiforme,
Stevens-Johnson syndrome)
• yellow skin or eyes, itching, or pain in the abdomen
(stomach) caused by inflammation of the liver
• breast enlargement in males
• angry behaviour, mood being affected, seeing or
hearing things that are not really there (hallucinations),
mania (mental condition characterised by episodes of
overactivity, elation or irritability), paranoia,
suicidal thoughts
• whistling, ringing or other persistent noise in the ears
• tremor (shaking)
• flushing
Tests may show:
• increased cholesterol in the blood
Rare (affects 1 to 10 users in 10, 000)
• itchy rash caused by a reaction to sunlight
• liver failure, in some cases leading to death or liver
transplant, has occurred with Efavirenz. Most cases
occurred in patients who already had liver disease, but
there have been a few reports in patients without any
existing liver disease
Combination antiretroviral therapy may change your
body shape, by changing the way body fat is distributed.
You may lose fat from your legs, arms and face, gain fat
around the abdomen (tummy) and other internal organs,
get larger breasts or fatty lumps on the back of the neck
('buffalo hump'). The cause and long-term health effects of
these conditions are not yet known.
Combination antiretroviral therapy may also cause raised
lactic acid and sugar in the blood, increased fat levels in
the blood (hyperlipaemia) and resistance to insulin. Your
doctor will test for these changes.
If you get any side effects, talk to your doctor or
pharmacist. This includes any possible side effects not
listed in this leaflet.
5. How to store Efavirenz
Keep out of the reach and sight of children.

Use in children and adolescents
The dose for children and adolescents weighing 40 kg or
more is 600 mg once daily.

Do not use this medicine after the expiry date, which is
stated on the blister or bottle after 'EXP'. The expiry date
refers to the last day of that month.

Other formulations of efavirenz are available for patients
who need some dose adjustment. You should refer to the
accompanying package leaflet of suitable formulations for
paediatric dosing (3 to 17 years).

This medicinal product does not require any special
storage conditions.

If you take more Efavirenz than you should:
If you take too much Efavirenz, contact your doctor or
nearest emergency department for advice.
Keep the medicine container with you so that you can
easily describe what you have taken.
If you forget to take Efavirenz:
Try not to miss a dose. If you do miss a dose, take the next
dose as soon as possible, but do not take a double dose to
make up for a forgotten dose. If you need help in planning
the best times to take your medicine, ask your doctor
or pharmacist.
If you stop taking Efavirenz:
When your Efavirenz supply starts to run low, get more
from your doctor or pharmacist. This is very important
because the amount of virus may start to increase if the
medicine is stopped for even a short time. The virus may
then become harder to treat.
If you have any further questions on the use of this
medicine, ask your doctor or pharmacist.
4. Possible side effects
Like all medicines, this medicine can cause side effects,
although not everybody gets them.
When treating HIV infection, it is not always possible to
tell whether some of the unwanted effects are caused by
Efavirenz or by other medicines that you are taking at the
same time, or by the HIV disease itself.
The most notable unwanted effects reported with
Efavirenz in combination with other anti-HIV medicines
are skin rash and nervous system symptoms.
You should consult your doctor if you have a rash, since
some rashes may be serious; however, most cases of rash
disappear without any change to your treatment with
Efavirenz. Rash was more common in children than in
adults treated with Efavirenz.

The in-use shelf-life of the product when stored in HDPE
bottles is 100 days.
Do not throw away any medicines via wastewater or
household waste. Ask your pharmacist how to throw away
medicines you no longer use. These measures will help
protect the environment.
What Efavirenz contains
The active substance is efavirenz.
Each film-coated tablet contains 600 mg of efavirenz.
The other ingredients are cellulose microcrystalline,
croscarmellose sodium, hydroxypropyl cellulose,
lactose monohydrate (see section 2 'Efavirenz contains
lactose'), silica colloidal anhydrous, magnesium stearate,
hypromellose (E464), macrogol 400, titanium dioxide
(E171), iron oxide yellow (E172) and iron oxide red (E172).
What Efavirenz looks like and contents of the pack
Efavirenz tablets are yellow, capsule shaped biconvex
bevelled edge film-coated tablets marked with 'M' on one
side and 'EV6' on the other side.
Efavirenz is available in blisters of 30, 60, 90, 100 filmcoated tablets, perforated unit dose blisters of 30 x 1 filmcoated tablets, and in plastic bottles of 30, 500 filmcoated tablets.
Not all pack sizes may be marketed.
Marketing Authorisation Holder:
Mylan, Potters Bar, Hertfordshire, EN6 1TL,
United Kingdom
Generics[UK] Limited, Potters Bar, Hertfordshire, EN6 1TL,
United Kingdom
Gerard Laboratories, 35/36 Baldoyle Industrial Estate,
Grange Road, Dublin 13, Ireland

The nervous system symptoms tend to occur when
treatment is first started, but generally decrease in the first
few weeks. In one study, nervous system symptoms often
occurred during the first 1-3 hours after taking a dose. If
you are affected your doctor may suggest that you take
Efavirenz at bedtime and on an empty stomach. Some
patients have more serious symptoms that may affect
mood or the ability to think clearly. Some patients have
actually committed suicide. These problems tend to occur
more often in those who have a history of mental illness.
Always notify your doctor immediately if you have these
symptoms or any side effects while taking Efavirenz.
Tell your doctor if you notice any of the following
side effects:
Very common (affects more than 1 user in 10)
• skin rash
Common (affects 1 in 10 users in 100)
• abnormal dreams, difficulty concentrating, dizziness,
headache, difficulty sleeping, drowsiness, problems with
coordination or balance
• stomach pain, diarrhoea, feeling sick (nausea), vomiting
• itching
• tiredness
• feeling worried, feeling depressed
Tests may show:
• increased liver enzymes in the blood
• increased triglycerides (fatty acids) in the blood

This leaflet was last revised in: 466985

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Source: Medicines and Healthcare Products Regulatory Agency

Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.