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DRUG
THERAPY
NSAIDS
– NON-STEROIDAL ANTI-INFLAMMATORY DRUGS
They are symptomatic anti-inflammatory, anti febrile (fever) and
analgesic (pain reducing) medications. Symptomatic means that
they do not affect the course of the disease, but serve to controls
symptoms.
They act mainly by blocking an enzyme, which is important for
the formation of substances that can cause inflammation.
On the other hand, these substances also have a physiological
role in the body that includes stomach protection and regulation
of blood flow in the kidney. These physiological effects explain
most of the side effects of NSAIDs.
These side effects include:
Gut problems. These are the most common side effect, causing injuries
to the lining of the stomach.
Symptoms range from mild abdominal discomfort after taking the
medication, to severe abdominal pain and bleeding from the stomach,
that may appear as black and loose stools.
Gastrointestinal side effects in children are poorly documented,
but in general are considerably less of a problem than those observed
in adults. NSAIDs have to be taken with food.
Side effects involving the liver can cause an increase in liver
enzyme, but it is hardly of significance except with aspirin.
Kidney problems are rare and only happen in children who have
had previous problems with the heart, liver or kidneys.
NSAIDs can affect blood clotting, but this is not clinically important
unless the child already has a blood clotting abnormality. Aspirin
is the drug that causes the most problems with blood clotting.
This side effect is exploited for the treatment of diseases in
which there is an increased risk of thrombosis (formation of pathologic
blood clots inside the blood vessels). In this case, aspirin in
low doses is the drug of choice.
Several
NSAIDs are available. Naproxen and Ibuprofen are widely used.
Aspirin, although cheap and effective, is less used nowadays because
of its side effects. NSAIDs are not used in conjunction with one
another.
Children will respond differently to different NSAID, so one NSAID
may be effective were another has failed.
Recently, another category of NSAIDs has been introduced in the
market, called COX-2 inhibitors (Celecoxib, Rofecoxib).
These drugs seem to have less gastric side effects than the other
NSAID, whilst maintaining the same therapeutic power.
COX-2 inhibitors are much more expensive than the other NSAIDs
and the debate on their relative safety and efficacy over traditional
NSAIDs is not yet concluded. The experience with these drugs in
children is very limited.
Cyclosporine
A
Cyclosporine A is an immunosuppressive drug, initially used to
prevent organ rejection in patients who underwent transplant operations.
It is a potent inhibitor of a group of white blood cells that
have a fundamental role in the immune response.
It can be given in liquid or pill form.
Side effects are quite frequent, especially at high doses and
may limit the use of the drug. They include renal damage, high
blood pressure, liver damage, gum enlargement, hair growth over
the body, nausea and vomiting.
Treatment with cyclosporine, therefore, requires regular clinical
and laboratory check-ups to assess these side effects.
Intravenous
immunoglobulins
Intravenous immunoglobulins (IVIG) are prepared from large pools
of plasma from healthy blood donors. Plasma is liquid component
of human blood. IVIG are the treatment for children who lack antibodies,
because of a defect in their immune system. However, through mechanisms
that are still unclear and may vary in different situations, IVIG
have also been shown to be helpful in some autoimmune and rheumatic
diseases.
They are given by intravenous infusion and, generally, represent
a safe therapy. Side effects are rare and include anaphylactoid
(allergic) reactions, muscle pains, fever and headache during
infusion, headache and vomiting about 24 hours after infusion,
this resolves spontaneously.
IVIG are free of HIV, hepatitis and most other known viruses.
Corticosteroids
Corticosteroids (CS) are a large group of hormones that are produced
by the human body. The same, or very similar, substances can be
manufactured synthetically and used for the treatment of various
conditions.
The steroid prescribed to children is not the same as those used
by athletes to enhance performance.
CS are very potent and rapidly acting drugs, suppressing inflammation
by interfering with immune reactions in quite a complex manner.
They are often used to achieve more rapid clinical improvement
of a patient’s condition, before other treatments start
to work.
Apart from their immunosuppressive and anti-inflammatory effects,
they are also involved in many other processes within the body,
e.g. in cardiovascular function and stress reaction, water, sugar
and fat metabolism and blood pressure regulation.
There are considerable side-effects, associated mainly with long-term
therapy with CS. It is very important that a child is under the
care of a physician who is experienced in the management of the
disease and in minimizing the side-effects of these drugs.
Dosages
and ways of administration.
CS can be swallowed, or injected into a vein, or given locally
by injection in to a joint or the skin).
Dose and route of administration are chosen according to the disease
to be treated, as well as the severity of a patient’s condition.
Higher doses, especially when given by injection, are powerful
and act rapidly.
Oral tablets are available in different sizes, containing different
amounts of the drug. Prednisone and prednisolone are most commonly
used.
There is no generally accepted rule for drug dosing and frequency
of administration.
A dose taken once a day or once every other day (in the morning)
has less side effects than a split dose taken at different times
of the day. A split dose can be more effective and is, therefore,
sometimes necessary to maintain control of the disease. In severe
disease, many physicians will prefer to choose high-dose methylprednisolone,
which is given as an infusion into the vein, usually once daily
for several days in a row.
Sometimes, daily intravenous administration of smaller doses may
be used when oral medication has not been effective.
Injection of long-acting CS into the inflamed joints is a treatment
of choice in arthritis, usually triamcinolone, acetonide, or hexacetonide.
These drugs have the active steroid substance bound on small crystals
that, after having been injected into the joint cavity, spread
around the inner joint surface and release CS over a prolonged
period. This often leads to a long-term anti-inflammatory effect.
Nevertheless, duration of this effect is highly variable lasting
weeks to months. One or more joints can be treated in one session
using combinations of skin anaesthetic cream, or spray, local
anaesthesia, sedation (midazolam, entonox), or general anaesthesia,
depending on the number of joints to be treated and the age of
the patient.
Side
effects
There are two main types of side effects that occur with CS: those
resulting from prolonged use of large doses and those resulting
from withdrawal of therapy. If CS are taken continuously for more
than about one month they cannot be stopped suddenly as this might
cause severe problems. This is because the body will stop producing
the steroids naturally during treatment and, if corticosteroids
are stopped suddenly, the body can take months to begin producing
the steroids in the amounts needed to maintain normal health.
The efficacy, as well as the type and severity of CS side effects,
are individual and are difficult to predict. The side effects
usually relate to the dose and administration regimen, e.g. the
same total dose would have more side effects if given in divided
daily doses rather than in a single morning dose.
The main visible side effects include, increased hunger, which
is difficult to control and can result in weight gain and the
development of stretch marks on the skin. Keeping a well-balanced
diet, low in fat and sugars and high in fibre, will help to control
weight gain.
Acne on the face can be controlled by skin treatment. Problems
with sleeping and mood changes, with feelings of being jittery
or shaky, are common. With long-term CS treatment growth is often
suppressed.
Defence against infections may also be altered, resulting in more
frequent, or severe, infections depending on the extent of immunosuppression.
Chickenpox may run a serious course in immunosuppressed children,
so it is very important to alert your doctor immediately when
your child either develops the first signs, or you realise that
he or she has been in close contact with someone who subsequently
develops the disease.
According to the individual situation injection of antibodies
against chickenpox virus, or anti-viral antibiotic can be given.
Most of the less obvious side effects may be revealed by close
monitoring during treatment. They include, loss of bone mineral,
causing the bones to become weaker, making the patient more prone
to fractures (osteoporosis).
Osteoporosis can be identified and followed by a special technique
called bone densitometry. It is believed that a sufficient supply
of calcium (about 1000 mg daily) and vitamin D may be useful to
slow down the evolution of osteoporosis.
Side effects involving the eye include cataract and glaucoma.
If increased blood pressure evolves, a low-salt diet is important.
Blood sugar levels can raise causing steroid-induced diabetes,
this is when a diet low in free sugars and fat is necessary.
AZATHIOPRINE
Azathioprine is a medication that decreases immunity.
It works by interfering with the production of DNA, a process
that all cells need in order to divide. The inhibition of the
immune function is, in fact, due to the effect of the drug on
the growth of one kind of white blood cells (lymphocytes.)
It is administered orally. Although usually better tolerated than
cyclophosphamide, it can have some side effects that need close
monitoring.
Gastrointestinal problems (oral ulcers, nausea, vomiting, diarrhea,
epigastric pain) are uncommon. Liver toxicity may occur, but is
rare. A reduction in the number of circulating white blood cells
(leukopenia) may occur and is dose related. The reduction in the
number of platelets, or red blood cells, is less comon.
The long term use of azathioprine may be associated with an increased
risk of cancer, but so far the evidence is not conclusive.
As with other immunosuppressive agents, treatment exposes the
patient to an increased risk of infections. Herpes zoster infection,
in particular, is observed with higher frequency in patients treated
with azathioprine.
Cyclophosphamide
Cyclophosphamide is an immunosupressive medication, which reduces
inflammation and suppresses the immune system. It works by interfering
with the multiplication of cells, altering the synthesis of DNA.
It is particularly active on those cells such as blood cells,
hairs and intestinal lining cells that multiply at a high rate.
White blood cells, called lymphocytes, are affected the most by
cyclophosphamide and their change in function and number explains
the suppression of the immune response. Cyclophosphamide has been
introduced to treat certain forms of cancer. In rheumatological
diseases, when it is used in intermittent therapy (given as a
monthly injection) it has fewer side effects than in cancer patients.
Cyclophosphamide is administered orally, or intravenously. In
this latter case, huge doses are usually given at four weekly
intervals.
Cyclophosphamide is a drug that greatly reduces immunity and has
several side effects that need close laboratory monitoring. The
most common are nausea and vomiting. Reversible thinning of the
hair can also occur.
Excessive reduction in the number of circulating white blood cells,
or platelets, may occur and may need dose adjustment or temporary
withdrawal of the drug.
Bladder problems may occur, but is much more common in patients
on a daily oral dose, rather than those on monthly injections.
To avoid this problem, plenty of water should be drunk.
Long term treatments run the risk of fertility impairment and
increased cancer frequency, depending on the cumulative dose of
the drug taken by the patient.
Cyclophosphamide reduces the immune defences and therefore increases
the risk of infections, especially, if given in association with
other agents that interfere with immunity, such as high dose corticosteroids.
Methotrexate
Methotrexate (MTX) is a drug used in children with a number of
different diseases for many years. It was initially developed
as a anti-cancer drug because of its ability to slow down the
rate of the cell division.
Nevertheless, this effect is only significant in higher doses.
In low intermittent doses, used in rheumatic diseases, MTX reaches
its anti-inflammatory effect through other mechanisms. When used
in such small doses, the majority of the side effects seen with
larger doses do not occur, or are easy to monitor and manage.
MTX is available in two main forms, tablets and as an injection.
It is given only once weekly, on the same day of the week.
The physician decides on the route of administration and dose
according to the individual patient’s condition.
Tablets are better absorbed when taken before a meal and, preferably,
with water. Injections can be administered just under the skin,
but can also be given into the muscle or vein.
Injections have the advantage of better absorption and less stomach
problems. MTX therapy is usually long-term. Most of the physicians
recommend treatment to continue for at least 6-12 months after
symptoms subside.
Most children on MTX have very few side effects. They include
nausea and stomach upset. These can be managed by taking the dose
at night. A vitamin, called folic acid, is often prescribed to
prevent these side effects.
Using anti-sickness drugs before and after the MTX dose, or changing
to the injected form, can help. Other side effects include mouth
ulcers and skin rash.
Coughs and breathing problem are rare side effects in children.
The effect on the number of blood cells, if present, is usually
very mild. Long term liver damage appears to be very rare in children,
because other liver toxins, such as alcohol, are not a problem.
Usually, MTX therapy is interrupted when liver enzymes increase
and re-started when they fall back to normal.
Regular blood tests are therefore needed during MTX therapy.
Although a risk of infections is usually not increased in children
treated with MTX, some of them may have a more serious course.
Among these, chickenpox, or shingles, seems to be of importance.
If your child has not had chicken-pox but comes in contact with
someone who develops it or if your child develops chickenpox you
should contact your physician immediately as a special medication
may be needed.
If your child is a teenager other considerations may become important.
They include alcohol intake which should be strictly avoided as
it may increase the liver toxicity of MTX. MTX may harm an unborn
baby so it is very important that contraceptive precautions are
taken when a young person becomes sexually active.
Hydroxychloroquine
Hydroxychloroquine was originally used for the treatment of malaria.
It has been shown to interfere with several processes related
to inflammation.
It is given as a once daily tablet and is usually well tolerated.
Gastrointestinal problems may occur, but are not severe. The main
concern is toxicity to the eye. Hydroxychloroquine accumulates
in the retina and persists for long period of time after treatment
has been discontinued.
These alterations are rare but may cause blindness even after
medication has been stopped. However, this eye problem is extremely
rare at the low doses currently used.
Early detection of this complication prevents visual loss if medication
is discontinued. Periodic eye examinations are necessary, although
there is a debate about the need and frequency of these controls
when hydroxychloroquine is administered at low doses.
Sulfasalazine
Sulfasalazine is a combination of an antibacterial and an anti-inflammatory
drug. It was conceived many years ago when adult rheumatoid arthritis
was thought to be an infectious disease. Despite the rational
for its use subsequently being revealed to be wrong, sulfasalazine
has been shown to be effective in some forms of arthritis as well
as in a group of diseases characterized by chronic gut inflammation.
Sulfasalazine is administered orally. Side effects are not uncommon
and require periodic blood tests.
They include gastrointestinal problems (anorexia, nausea, vomiting
diarrhoea), allergy with skin rash, liver problems, a reduced
number of circulating blood cells and a decrease in serum immunoglobulin
concentrations.
This drug should never be given to systemic Juvenile Idiopathic
Arthritis, or Juvenile Systemic Lupus Erythematosus patients,
because it can induce severe flares of these diseases.
Colchicine
Colchicine has been used for centuries. It inhibits the function
and numbers of white blood cells, blocking inflammation.
It is given orally. Most of the side effects are related to the
gastrointestinal system. Diarrhea, nausea, vomiting and occasional
abdominal cramps may improve with a lactose-free diet. These side
effects usually respond to a short term dose reduction.
After the disappearance of these signs, an attempt to slowly increase
the dose to the original level can be made. There might be a decrease
in the number of blood cells, therefore, periodic tests for blood
cells counts are required.
Muscle weakness may be seen in patients with renal or liver problems.
Prompt recovery is achieved after discontinuation of the drug.
Another side effect is damageto the peripheral nerves (neuropathy),
and, in these rare cases, the recovery may be slower.
Rash and alopecia may also be observed occasionally.
Serious intoxication may occur after ingestion of high amounts
of the drug. The treatment of colchicine intoxication requires
medical intervention. Gradual recovery is usually observed, but
sometimes it may be fatal. Parents should be very cautious that
the drug is not within the reach of small children.
Colchinine treatment in Familial Mediterranean Fever is continued
throughout pregnancy. If there are additional risks factors an
amniocenthesis in the third to fourth month of the pregnancy (testing
for abnormal chromosomes from a small sample obtained from the
fluid surrounding the baby) should be performed.
Anti
– TNF agents
Tumor necrosis factor (TNF) is a molecule that plays a central
role in the inflammatory process. Thanks to modern biotechnology
different type of medications that selectively inhibit TNF have
been produced.
These include antibodies against TNF (infliximab and adalimubab)
and TNF receptor blockers (etanercept).
Etanercept is administered by a subcutaneous injection. Patients,
as well as family members, can be taught to self-administer these
injections. Local reactions (red spot, itching, swelling) may
occur at the site of injection. These reactions are usually of
short duration and mild intensity.
Infliximab is administered intravenously in a hospital setting.
During the infusion an allergic reaction may occur going from
mild reaction (shortness of breath, red skin rash, itching) that
are easily treated, to serious allergic reactions with hypotension
(lowering of the blood pressure) and the risk for shock.
These allergic reactions occur most frequently after the first
infusion and are due to an immunization against a portion of the
molecule. If an allergic reaction occurs, the drug is withdrawn.
Adalimubab is the same as infliximab and is administered by a
subcutaneous injection.
All these drugs have a potent anti-inflammatory effect that persists
as long as they are administered. Side effect are mainly represented
by a greater susceptibility to infections, especially tuberculosis.
Evidence of serious infectious should lead to drug withdrawal.
In some rare instances treatment has been associated with the
development of autoimmune diseases other than arthritis.
Since the experience with TNF-inhibitors is recent, long term
safety data is still lacking.
These therapies are frequently referred to as biological agents,
because they are produced by biotechnologies.
There are other such agents like IL1ra and IL6 antibodies that
are being used in the treatment of some adult rheumatic diseases
and, experimentally, in children.
All biological agents are very expensive.

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