Do cold remedies contain caffeine? why?

Caffeine is well known as the stimulant component of coffee. However, in fact, many of the medicines we commonly encounter contain caffeine. In particular, it is often contained in comprehensive cold medicine, but what role does this caffeine play? Pharmacist Kim Ji-young explained.

Common cold medicines sometimes contain caffeineㅣSource: Getty Image Bank
Comprehensive cold medicine is a mixture of various ingredients to relieve cold symptoms. In general, analgesic and antipyretic components are used to relieve symptoms such as fever, headache, sore throat, and joint pain, and antihistamines are used to relieve allergic reactions such as nasal congestion, sneezing, and conjunctivitis. The biggest reason caffeine is added to cold medicine is because of this antihistamine.

Histamine is a neurotransmitter that acts on the central nervous system and contributes to maintaining alertness. In allergic or inflammatory reactions, excessive secretion of histamine causes symptoms such as stuffy nose and sneezing. Antihistamines alleviate these reactions, but at the same time suppress the arousal action of histamine, causing central nervous system side effects such as drowsiness. Some cold medicine products contain caffeine to prevent sleepiness after taking an antihistamine. Caffeine stimulates the central nervous system to prevent drowsiness and induce wakefulness.

When the brain is active, a substance called adenosine is produced, and when this substance binds to the receptor, the activity of nerve cells decreases, which can make you feel sleepy. Caffeine has a similar structure to adenosine, so it can bind to nerve cell receptors instead of adenosine. When caffeine binds to receptors instead of adenosine, the action of nerve cells is not hindered, so side effects such as drowsiness can be suppressed.

Caffeine also increases the release of dopamine, one of the neurotransmitters. Dopamine can exert an arousal effect by acting as a central exciter. When you catch a cold, there are many cases accompanied by a headache. At this time, caffeine works by constricting blood vessels to relieve headache symptoms.

Caffeine suppresses the side effects of cold medicine, but it also maximizes the effect of cold medicine. When caffeine stimulates the central nervous system, blood circulation is promoted, so drug ingredients are quickly delivered to the body.

However, caffeine is a stimulant and can cause sleep disturbances if taken at night. Resting and sleeping well is especially important when you have a cold. This is because it boosts the immune system and helps the body recover. Therefore, in the evening, choose a product that does not contain caffeine and take it.

When taking cold medicine, avoid foods that contain caffeine, such as coffee, chocolate, and green tea. This is because you may exceed the recommended daily dose. It is usually recommended that adults consume no more than 400 mg of caffeine per day. Pregnant women should be more mindful of their caffeine intake. Excessive intake of caffeine during pregnancy can negatively affect the growth of the fetus, so the daily recommended amount is limited to 200-300 mg. Pharmacist Ji-Young Kim finished the explanation by saying, “I hope you take it safely by checking the contents written in the instruction manual or package.”