Dr C P Ravikumar

Side effect

Side effect – the word itself makes every patient or parent worry immensely even if it doesn’t occur. Any medication that is prescribed to a patient has some counter-effect on the body despite it being used for treating a condition. It is important to know and understand the very concept of “side-effects” rather than being paranoid about it. This blog is an attempt to explain what it means and why it is important to be aware of the side effects of any treatment or therapy any patient is subjected to.

What is a side effect?


There are many ways to define what a side effect means; The National Cancer Institute (NCI) defines a side effect as “an unexpected medical problem that happens during treatment with a drug or other therapy.”

In simple terms, a side effect is an effect of the medication or treatment that is UNWANTED.

Let us look into some common questions and myths around the same.

Q. Are a side effect and an allergic reaction the same?

No, they both are separate and different entities. Let us not mix them up.

Q.Which medications/therapies cause side effects?

Anything that has an effect also carries a risk of side effects! There is no medicine that does not have side effects. Hence it is essential to accept that a side effect is the other side of an effect. It is a risk that is carried by every medicine – allopathic, homeopathic, over-the-counter medications, or prescribed medications.

Q. Why are drugs with side effects allowed for use?

All drugs go through a stringent approval process before they get approved for use, only drugs for which the benefits are far greater than the side effects are approved. It is important to reiterate that an impact and a side effect are two sides of a coin!

Q. What are some examples of side effects?

Side effects can be mild to severe. For example, antibiotics are associated with causing Gastritis, and diarrhea as common side effects, here the benefit of antibiotics outweighs the side effect. Hence, it is accepted and generally, so the patient doesn’t need to worry too much. Serious side effects of antibiotics include effects on heartbeat, and suppression of blood cell production, which can be severe, and uncommon.

Each drug has its set of known side effects and several UNKNOWN SIDE EFFECTS, for more information, it is best to read about the side effects of the specific medicine you may be taking or have been prescribed.

Q. Am I more prone to side effects in general?

To start off, all of us carry the same risk of having side effects and also the beneficial effect of the medicine, however, our genes, general health, and other factors that are unique to each one of us will determine if we will face a side effect of the drug or not.

Q. Can I know about the side effect that I can experience, beforehand?

As a rule, we don’t have a test or a way to know before a side effect can occur in anyone.

Pharmacogenomics is a fast-evolving field of medicine, which can help us identify individuals at greater risk of side effects of specific drugs. We have some drugs which are very effective but carry serious side effect, which we now know is more likely to happen in individuals with a specific gene. So, gene testing is an option for a few drugs.

Example: *HLAB1502* gene carriers have a high chance of having serious life-threatening side effects with Carbamazepine, which we can test before advising the medication.

Q. Will I experience side effects after taking the first dose?

It can’t always be predicted but usually, side effects take a few days to develop, and allergic reactions can happen after first exposure. Sometimes, side effects may occur only at a higher dose.

Q. I am taking a specific medication and have not experienced any side effects so far, does it mean I will never face any side effects with this drug?

It is very likely true that you may not have to face any side effects with this drug. However, it doesn’t mean throwing caution to the wind. There is a possible risk of side effects due to long-term use, increasing dose, other medications, or other health issues. It’s like driving a vehicle, you always must have situational awareness, but that doesn’t mean you worry throughout your entire journey about getting involved in an accident.

Q. Do generic medications carry an extra risk of side effects?

Generic medicines are basically copies of branded drugs, they are expected to have the exact effect, and side effects as the original drug.

Q. Where can I get more information about the side effect of the medicine I am to take/or am taking?

Searching on the web may give rise to information overload, your doctor or the drug information insert that accompanies most prescription medicine will be your best source of information.

Q. What does a common side effect and a rare effect mean?

WHO and other international organizations use terminologies that make people and healthcare professionals speak the same language. When a side effect is defined as very common it means in every 10 patients taking a medicine, 1 or more will have side effects Very common: 1 on 10 Common (frequent): 1 in 100 Uncommon (infrequent): 1 in 1000 Rare: 1 in 10000 Very rare: less than1 in 10000 To give perspective on life, Bengaluru recorded 4688 “registered” accidents in 2019 (as per Bengaluru Traffic Police statistics), meaning it is more likely to get involved in an accident than the side effects of medication.

Q. Will other medications I take, cause an increased risk of side effects?

If it is possible, please discuss with your doctor the potential risks before you start any new medication.

Q. What are adverse drug reactions (ADR)?

An adverse drug reaction is an unwanted or harmful reaction experienced following the administration of a drug and is suspected to be related to the drug. An ADR will usually require the drug to be discontinued or the dose reduced.

A side-effect is an effect caused by a drug other than the intended therapeutic effect, whether beneficial, neutral or harmful.

Q. What is a drug interaction?

Drugs can interact with another drug if you are on multiple medications, drug effects can be modified by food and your health. This topic is too complex to be generalized. Some examples are as below.

Cough syrup Benadryl has a sedating effect, the effect can be amplified if you are taking Clobazam (medicine to stop seizures)

Tea can reduce the absorption of iron, whereas Vit C-rich food can increase its absorption.
Nose decongestants are commonly prescribed for blocked nose, they contain Phenylephrine which may worsen blood pressure or raise Blood pressure if someone is already prone to having high B.P.

Q. Well, after reading this, I am afraid to take any medicine!

The reality is that these side effects/interactions/ adverse reactions have existed from the time medicines were introduced. The current generation has access to information from varied sources, which are not always reassuring, hence an attempt has been made to simplify.

The current generation wants to know all and worry about it!

If you are concerned, speak to your doctor, know what is relevant, what you can do about and move on with improving your health and life!

Remember, Forewarned is forearmed!
Dr C P Ravikumar

Dr C P Ravikumar

CONSULTANT – PEDIATRIC NEUROLOGY
Aster CMI Hospital, Bangalore