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It is important to
note that if you consult a rational doctor and inform him/her regarding
your medical history in detail, it is most likely that he/she may prescribe
the correct drug for you, which is less likely to produce an harmful adverse
effects. While it is true that no drug is safe and even the mildest drug
can produce serious adverse effects if misused or abused, most drugs will
not cause serious harm if used correctly.
Just because
a drug can produce certain adverse effects one should not hesitate to
use it, when it has been prescribed by the doctor. The adverse effects
of drugs are listed down in this column as a measure of precaution and
not to create panic amongst the users.
IX.
Interactions
Whenever
a drug is taken along with other drugs or certain foods or alcohol, it
is likely that the drug may interact with them and produce effects which
are entirely different from those produced when it is taken alone. Many
times these interactions may produce beneficial effects which are utilised
in the treatment of the patient, for example, for the treatment of high
blood pressure, usually more than one drug is prescribed. Other interactions
may produce harmful and unwanted effects and hence their occurrence should
be avoided. Such interactions may occur not only between two prescription
drugs but also between OTC drugs and prescription drugs. It is therefore
necessary to read the warnings on the labels of drugs which you are taking
and also inform your doctor about all other drugs that you are taking
when s/he is prescribing a drug for you. This helps the doctor to choose
the right drug for you, which will not interact with other drugs you are
taking or at least suggest a dosage regimen where the doses of the two
drugs are spaced far enough to avoid an interaction.
Examples
of Important (Dangerous) Interactions
| (1) |
|
Drugs that depress the central nervous system(sleep
inducing drugs, narcotics, antihistamines
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and alcohol). The effect of two or more
of these in combination may be additivecausing dangerous oversation.
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| (2) |
|
Drugs
that lower blood sugar levels and suchdrugs
as sulfonamides and alcohol. The druginteraction
increases the effect of blood sugarlowering
drugs, thus further depressing bloodsugar
levels.
|
| |
|
| (3) |
|
Oral anticoagulants and other drugs, particularly
aspirin
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and
antibiotics. Because thesedrugs
may increase the tendency to bleed, it is essential
to check the effects in every case.
|
| (4) |
|
Monoamine
Oxidase Inhibitors (MAOIs): Thereis
a large |
| |
| |
|
list of
drugs and foods which can produce a severe rise in blood pressure
when taken with these drugs. Dangerous drugs include amphetamines
and decongestants. Foods that interact include cheese, herring, red
wine, beer and chocolate. |
|
|
This column lists
down only the important interactions of the drug with other drugs. (Its
interactions with food, alcohol, tobacco, etc., are mentioned under 'Precautions').
The final effect of drug-drug interaction is mentioned along with explanatory/warning
notes wherever necessary.
Drug-Nutrient
Interactions
|
| Medication |
Use |
Effect
on Nutritional Status
|
| Alcohol |
Toxic
effect on intestinal lining, altered secretion of digestive enzymes |
Reduced
absorption of vitamin B1, folic acid, vitamin B2, increased excretion
of magnesuim
and zinc; reduced blood
levels of vitamin
B12. |
Amitriptyline
Imipramine
Lithium carbonate |
Antidepressant |
Weight
gain; altered blood glucose; increased
blood levels of magnesium;
increased excretion of calcium. |
| Amphotericin
B |
Antifungal |
Increased
urinary excretion potassium and nitrogen; reduced blood levels of
magnesium and potassium. |
| Antihistamines |
Nasal
Congestion |
Increases
appetite |
| Barbiturates |
Anticonvulsant |
Increased
need for folic acid and vitamin D; reduced absorption of vitamin B1;
increased excretion of vitamin C. |
Biouanides
Metformin, Phenformin |
Diabetes |
Reduces
absorption of vitamin B12 |
| Chloramphenicol |
Antimicrobial |
Increased
need for vitamin B2, vitamin B6, and vitamin B12. |
| Chlorpromazine |
Tranquilizer |
Increased
appetite and body weight. |
| Colchicine |
Anti-inflammatory |
Reduces
absorption of carotene, sodium, potassium, vitamin B12, lactose.
|
| Colocynth |
Cathartic |
Reduces
transit time and absorption of nutrients. |
| Corticosteroids |
|
Reduced
absorption of calcium and phosphorus; increased urinary excretion
of vitamin C, calcium, potassium, zinc, and nitrogen; reduced blood
levels of zinc; increased blood |
|