OTC Drugs: Reducing the Risk of Adverse Effects

What does it mean to have an adverse effect from an OTC drug?
You can buy over-the-counter (OTC) medicines without a doctor's prescription. OTC drugs can help treat or prevent symptoms from illness or other health problems, such as allergies. However, sometimes OTC drugs cause problems. These problems are called adverse effects. Adverse effects from OTC drugs include side effects, drug-drug interactions and food-drug interactions.
Because the possible adverse effects are different from one OTC drug to another, you must read the label of any OTC product carefully to know what to expect.

What is a side effect?
Side effects are effects that drugs have on your body that don't help your symptoms. Side effects are most often not pleasant. They may include nausea, feeling dizzy, bleeding in your gastrointestinal (GI) tract and others.
Sometimes, side effects can be useful. For example, certain antihistamines can cause sleepiness. This might be bad for people who take antihistamines during the day to treat allergies. But if you are taking an antihistamine at nighttime, this side effect might help you get the sleep you need.

What is a drug-drug interaction?
One type of adverse effect can happen when 2 or more drugs are taken at the same time. This is called a "drug-drug interaction. " The body processes every drug differently. If 2 or more drugs are used at the same time, the way your body processes them can change. When this happens, the risk of side effects from each drug increases.

Do you know what's in the medicines you take?
Many OTC drugs contain the same ingredients found in prescription drugs. By combining OTC drugs with other OTC drugs or with your prescription medicine, you may be getting more than the recommended daily dose of the active ingredient (the substance in the medicine that works to relieve your symptoms). If you have any questions, ask your family doctor or pharmacist.

What is a drug-food interaction?
Drugs can cause problems when they are taken with certain foods or drinks. This is called a "drug-food interaction. " Drug-food interactions can happen with prescription medicines and with OTC drugs, including antacids, vitamins, iron pills and others.
Sometimes the food you eat affects the ingredients in a medicine you're taking and prevents the medicine from working the way it should. This can be dangerous. For example, if your blood pressure medicine isn't working the way it should, your blood pressure could rise and cause serious problems.
Other times, combining drugs with certain foods or drinks can make side effects worse. For example, taking certain OTC antihistamines while drinking alcohol can increase the side effect of drowsiness. In older adults, this type of drug-food interaction can increase the risk of falling.

Are all OTC drugs affected by food?
No. But many OTC drugs can be affected by what you eat and when you eat it. For example, if you take certain drugs at the same time that you eat, your food may get in the way of how your stomach and intestines absorb the medicine. This is why some drugs should be taken on an empty stomach (1 hour before eating or 2 hours after eating). On the other hand, it's easier for your body to process certain drugs when you take them with food.
Read the drug label to see if you should take your medicine with a snack or a meal, or if it should be taken on an empty stomach. If the label doesn't give specific directions, taking the drug with or without food probably won't affect the way the drug works. If you have any questions, ask your family doctor or pharmacist.

Should I avoid certain activities when I'm taking an OTC drug?
Some OTC drugs can cause adverse effects if you do certain activities while using the drug. For example, some drugs cause sun sensitivity. This makes it easier for you to get a sunburn or sun rash. You may need to limit how much you're outdoors or protect your skin from the sun while taking the medicine.
Another example involves certain antihistamines. These medicines can cause sleepiness. You should wait until you know how these drugs affect you before you drive or run machines. Be careful. Antihistamines may slow your reactions without you even being aware of it.
As with other adverse events, these types of warnings are different for different products. Read the label to find out what you need to know before taking any OTC product.

How will I know I'm having an adverse drug reaction?
When you're taking any medicine, it's important to be aware of changes in your body and how you feel. If you have any concerns, call your family doctor. It may be hard to know whether a certain symptom is caused by your illness or by an adverse effect from your medicine. Tell your family doctor when the symptom started and if it is different from other symptoms you have had. Be sure to tell your family doctor about all the medicines and herbal health products you're taking.

Allergic Reactions
It's not common, but some people can be allergic to a drug. If you've ever had an allergic reaction to a drug, be sure to avoid products that contain the same ingredient. Signs of an allergic reaction include itching, hives and trouble breathing. Call your family doctor right away if you think you' re having an allergic reaction.

Can adverse effects happen to anyone who takes an OTC drug?
Anyone can have an adverse drug effect. However, some people are at higher risk. If you take more than 3 or 4 medicines every day, you're at higher risk of having a drug-drug interaction. The risk is even higher if you take any prescription drugs.
Others at higher risk of adverse effects include children, older adults and people who have health problems. Examples of health problems that put you at higher risk include the following:
* Breathing problems, such as asthma, emphysema or bronchitis
* Bleeding disorders
* Diabetes
* Enlarged prostate gland
* Epilepsy
* Glaucoma
* Gout
* Heart disease
* High blood pressure
* Immune system problems
* Kidney disease
* Liver problems
* Parkinson's disease
* Psychiatric problems
* Stroke
* Thyroid problems

How can I avoid adverse drug effects?
The best thing you can do to avoid adverse effects is to read the label carefully before taking any OTC drug. Be sure you understand all of the information. If you have any questions, ask your family doctor or pharmacist. Also, try to limit how often you use OTC products. Don't use them unless you really need them.
Tell your doctors (if you see more than one) about all of the medicines you're taking-even if you take something for just a short time. Include any herbal health products and vitamins and minerals you're taking. At least once a year, bring all of your medicines and supplements with you when you see your family doctor.
Keep track of any allergies and adverse reactions you have had to an OTC drug in the past. Check drug labels and avoid products that contain the same ingredients. This can help you avoid taking a medicine that may harm you. Remember that even if you didn't have a reaction to a medicine you took in the past, you could have a reaction when you take it now.

Tips on Reducing the Risk of Adverse Drug Effects

• Read the drug label carefully.
• Make sure you know what ingredients the product contains and understand any warnings or possible adverse effects.
• If you don't understand something, ask your family doctor or pharmacist about it.
• If you take any prescription drugs, ask your family doctor before taking an OTC drug.
• Don't stir medicine into your food or take capsules apart (unless your family doctor tells you to). This may change the way the drug works.
• Don't take vitamin pills at the same time you take medicine. Vitamins and minerals can cause problems if taken with some drugs.
• Don't mix medicine into hot drinks unless the label tells you to. The heat may keep the drug from working as it should.
• Don't take medicine with alcoholic drinks.

[AAFP]