Brief Answer:
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Detailed Answer:
Hi and Welcome to Ask A Doctor service. Thanks for using this app. I have read your question and here is my advice.
Yes, you are right constipation is a very common side effect of opioids and may be quite problematic. It's said about 80 percent of people do have constipation with opioids. Unfortunately, the effect continues to occur as long as you use the drug. For this reason, the recommendation is that we should prescribe drugs for constipation to patients who use opioids.
There are many drugs now available OTC for the relief of constipation caused by opioids. These include laxative (drugs that move the bowels) and stool softeners. Besides taking more fluid, we can use these drugs for it. The best is a combination of laxative and stool softener available over the counter. You can use the only laxative like senna, or sodium pyrosulphate or castor oil or softener like duphalac. You may talk to your pharmacist to tell you which may be best for you. But this would be needed until you use opioids.

Regarding the high potassium, opioids do not a use high potassium so until it is seen, or there is another reason for high potassium you should not worry about it. There is no need to take lasix(for high potassium) if not otherwise indicated.

Regarding the ectopic, yes opioids may cause fast heart rate but mostly settle with time and if you don't feel chest pain with it, or too much palpitation, or any syncope then there is no need to worry. Ectopic is mostly not serious. But if in doubt you can get an ECG.

Hopes this answer help you understand your query. Let me know if you have any further questions about it. I would be glad to answer that question.

Kind regards

Dr. Rahman

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