Respiratory stimulants: Nursing pharmacology

Definitions & Key takeaways

Respiratory stimulants are medications that are used to increase or improve breathing in individuals who have respiratory disorders or conditions. These medications can be used to treat a variety of conditions, including asthma, chronic obstructive pulmonary disease, or respiratory depression; as well as to treat apnea of prematurity.

Respiratory stimulants primarily work on the brainstem and medulla by stimulating the respiratory center, or act on the lungs by causing bronchodilation. Respiratory stimulants include drugs like doxapram, caffeine, theophylline, and aminophylline. Some common side effects can include muscle tremors, agitation, anxiety, irritability, and insomnia.

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Introduction0:00–0:32

Respiratory stimulants are a group of medications that can be administered to clients with asthma, chronic obstructive pulmonary disease or COPD for short, or respiratory depression; as well as to treat apnea of prematurity.
Respiratory stimulants include doxapram, which is administered intravenously, as well as certain phosphodiesterase enzyme inhibitors, also known as methylxanthines, such as caffeine, theophylline, and aminophylline, which are most often taken orally, but they can also be given intravenously.
Once administered, these medications primarily work on the brainstem and medulla by stimulating the respiratory center, and thus act as respiratory stimulants.

Mechanism of action0:32–0:51

In addition, methylxanthines can also act on the lungs by inhibiting the phosphodiesterase enzyme, and ultimately cause bronchodilation.Side effects commonly caused by respiratory stimulants include muscle tremors, agitation, anxiety, irritability, and insomnia.

Side effects0:51–1:25

Clients might also experience gastrointestinal disturbances like nausea, vomiting, and diarrhea. These drugs may also cause hypertension, heart palpitations, tachycardia, and ECG abnormalities.
In addition, theophylline has a very narrow therapeutic window, meaning it's very easy to overdose, and can cause arrhythmias or seizures.
Finally, administering high doses of caffeine to premature infants can lead to intracranial hemorrhage.As far as contraindications go, respiratory stimulants are contraindicated in clients with severe arteriosclerosis, symptomatic cardiovascular disease, and moderate to severe hypertension.

Contraindications & cautions1:25–2:16

Respiratory stimulants should also be avoided in clients with a history of seizures, as well as hepatic or renal disease.
Additional precautions should be taken during pregnancy and breastfeeding. Regarding interactions, theophylline and phenytoin should not be used together, as they decrease each other’s effects.
Finally, theophylline should not be combined with beta blockers, beta adrenergic agonists, antidepressants, H2 blockers like cimetidine, or certain antibiotics like ciprofloxacin, as well as tobacco smoke and marijuana, since these medications can increase the levels of theophylline and result in toxicity.
Due to the dangerous potential side effects, theophylline is now rarely used. Now, when caring for a client who is prescribed a respiratory stimulant like theophylline to improve their respiratory function, first perform a baseline assessment, including vital signs, especially respiratory rate, as well as SpO2, and lung sounds.

Nursing considerations & client education2:16–3:48

Then, review your client’s recent laboratory test results, including renal and hepatic function. Next, explain to your client that the medication will help them to breathe easier, and instruct them to take their medication daily, in the morning with or without food.
Be sure to let your client know that while taking theophylline, they should also avoid smoking, consuming alcohol, and dietary sources of caffeine, including coffee, tea, soda, and chocolate.
Then, review with your client some of the side effects they could experience during therapy, such as nausea, fast heartbeat, palpitations, irritability, anxiety, and insomnia.
Prompt your client to contact their healthcare provider if these side effects are persistent or if they become severe. In addition, emphasize the importance of reporting symptoms of theophylline toxicity, which could manifest as dizziness, lightheadedness, fatigue, weakness, and shortness of breath.
Finally, while your client is being treated with a respiratory stimulant like theophylline, monitor their vital signs and blood concentration levels of the medication, ensuring levels don’t exceed the therapeutic level of 20 mcg/mL; and keep a close eye out for the development of side effects.
Lastly, be sure to evaluate for the desired therapeutic response to the medication, including improved airflow and decreased respiratory effort.
Alright, as a quick recap… Respiratory stimulants are a group of medications that can be administered to clients with asthma, chronic obstructive pulmonary disease, or respiratory depression; as well as to treat apnea of prematurity.

Review3:48–4:33

These medications primarily work on the brainstem and medulla by stimulating the respiratory center, and can also act on the lungs by causing bronchodilation.
Some common side effects can include muscle tremors, agitation, anxiety, irritability, and insomnia. When caring for a client taking a respiratory stimulant, nursing considerations include performing a baseline assessment, monitoring for side effects, and evaluating for the desired therapeutic response.
Client teaching includes safe self-administration, as well as learning to recognize side effects, and when to contact the healthcare provider.