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Respiratory Pharmacology Review Pt 3: Methylxanthine Effects

Nurse Mike (Mike Linares)
By SimpleNursing | Published October 8th, 2018
Published October 8th, 2018
White pills poured out of a purple bottle.

Theophylline, the well-known methylxanthine drug, is going to be discussed in this article along with its effects on the body and adverse reactions.

What are Methylxanthines?

Methylxanthines are drugs used to treat lung conditions such as COPD and asthma by controlling the wheezing and preventing difficulty of breathing.

Theophylline helps to relax smooth muscles, widening the passages for breathing, and decreasing the irritant response of the lungs. Methylxanthines are bronchodilators that reverse bronchospasms. To become more potent, these drugs must be used regularly because it does not work immediately, unlike prescribed inhalers that offer quick relief.

A Study Technique

When it comes to creating useful study materials in nursing school, there are no rules. You can stick with tips or recall techniques that work for you. It’s an open field. That said, our way of easily memorizing and recognizing methylxanthines is to think of methamphetamines. Meth can make you feel things which you can associate with “Theo-feeling” or Theophylline. Moreover, methylxanthines usually end in “-phylline.”

There are certain similarities of methylxanthines to methamphetamines; however, you have to remember that methylxanthines are not illicit drugs. We are merely associating them with meth to help you recall methylxanthines easier. Methylxanthines like methamphetamines increase the rate of the heart.

How the Drug Works

Upon administration of theophylline, bronchodilation will occur. Opening up the respiratory pathways will subsequently affect the heart rate because, like caffeine’s effects, the heart will beat faster and the lungs will breathe better. Caffeine induces the sympathetic response of the body, opening up the lungs and triggering the heart’s rhythm to increase; which is why caffeine is suggested for those who have plans of going to the gym.

How Methylxanthines are Taken

Client teaching is usually focused on how to take the medication and the side effects that are more likely to happen.

In ingesting methylxanthines, advise your clients that these drugs are taken orally, either with or without the presence of food, depending on the doctor’s orders. For those who are experiencing stomach irritability after taking the drug before meals, it is best to take the medication while eating. Do not increase the dosage, use the drug as often as you could, or discontinue without informing the doctor.

If the clients do not feel relief or if the symptoms of asthma worsen, instruct them to consult the doctor immediately.

The Adverse Effects

All respiratory drugs can cause an upset stomach, specifically the sympathomimetic medications. Aside from that, there are a couple of side effects that clients will experience, namely:

  • Constipation
  • Insomnia
  • Irritability
  • Nausea and vomiting
  • Headache
  • Caffeine effects – restlessness, palpitations, nervousness

While these side effects are expected, some do not experience them at all. Some of the adverse reactions that need immediate medical attention are:

  • Continuous nausea and vomiting
  • Irregular or erratic heartbeat
  • Confusion and dizziness
  • Fainting and muscle cramps

Drug Precautions

It is imperative that clients promptly inform their physicians if they are allergic to caffeine or methylxanthines.

That’s it for our methylxanthines review. For other respiratory lectures and nursing-related topics, you can visit our SimpleNursing website and YouTube channel.

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Nurse Mike (Mike Linares)
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