@cathy514 I agree with Colleen and Teresa that you need to discuss your symptoms with your doctor or pharmacist. Medications can affect heart rate and some of my asthma inhaled medications can do that, so I use lesser dosages when I need to use them. I have a nebulizer and use a pediatric dose rather than an adult dosage prescribed by my doctor.

I'd also like to suggest some other reasons for a fast heart beat that I have experienced. If you have allergies or asthma and build excess phlegm in your lungs that gets trapped and interferes with oxygen absorption, this can raise your heart rate. I have had a problem like this because one side of my chest is too tight and doesn't expand enough, so I'm not moving the lung tissue enough, and I don't always move the mucous out like I should, and it is worse when I am exposed to seasonal allergies. The trapped phlegm can easily become a chest infection, and I have taken myself to an emergency room for this with my heart rate over 100 beats per minute at rest, and it became a repeating pattern of illness, and antibiotics resolved it. It was only after my allergy medicine and inhalers were not doing enough that I considered a chest infection as a cause, and I would notice my heart start to race when I was going up a flight a stairs and it would get worse in a few days. it usually starts as a sinus problem that moves into my lungs, and I try to prevent this with saline nasal rinses at the first sign of sinus congestion and to prevent and avoid allergy triggers.

Other causes can be related to blood pressure or dehydration. If you are dehydrated, your heart rate will increase. Make sure that you are drinking enough water. Your blood volume will decrease if you are dehydrated, and your heart will pump faster. If you have a lot of chest congestion, Mucinex or a generic version of that thins the mucous and makes it easier to expel and is available over the counter and you need to drink water to make it work. Last week I was on a trip in the mountains at a higher altitude, and my heart rate was elevated because I was not used to living where there was less oxygen available. Your heart has to compensate to adjust for your body's need for oxygen in relation to the available oxygen, and there is less oxygen available to the body at a high altitude or when chest congestion limits absorption. With colder temperatures now, the air inside our homes is a lot drier because cold outside air doesn't hold as much moisture, and it becomes drier as it's heated. To compensate for this, you can use a humidifier and you should drink more water. My elderly mom has also had some issues of heart acceleration because of dehydration that sent her to the hospital.

Here are some links about dehydration
https://www.mayoclinic.org/diseases-conditions/dehydration/symptoms-causes/syc-20354086
https://www.mayoclinic.org/diseases-conditions/dehydration/diagnosis-treatment/drc-20354092
https://www.emedicinehealth.com/dehydration_in_adults/article_em.htm#what_is_dehydration_in_adults