Needing help with myasthenia gravis

Katydidit34 · Oct 1, 2005

I don't know if this will help but Atropine is an antichonergic/antimuscarinic and one of its effects is to dry out secretions. Prednisone is used for its immunosuppressive properties. I hope this helps. Good luck!!

I am taking a physiology class along with my nursing classes. I know, call me crazy! In phys class we have case studies we have to answer questions on. So I have a question.
Why are nausea, abdominal cramps, diarrhea, and excessive salivation all side effects of the an anticholinesterase drug taken to improve a muscle disorder? What is the benefit of administering atropine and the corticosteroid, prednisone?

IVyPush-her · Oct 1, 2005

Hi, after looking around some of my notes and websites from nursing school, this is what I have come up with.

Anticholinesterase drugs prevent ACh destruction and increase the accumulation of ACh at neuromuscular junctions, improving the ability of the muscles to contract.

Its true that the side effects include excessive salivation, involuntary muscle twitching (fasciculation), abdominal pain, nausea, and diarrhea. A drug called kaolin may be used with anticholinesterase medications to reduce gastrointestinal side effects.

Corticosteroids (e.g., prednisone) suppress the antibodies that block AChR at the neuromuscular junction and may be used in conjunction with anticholinesterase. Corticosteroids improve symptoms within a few weeks and once improvement stabilizes, the dose is slowly decreased.

Atropine inhibits the muscarinic actions of acetylcholine on structures innervated by postganglionic cholinergic nerves, and on smooth muscles which respond to endogenous acetylcholine but are not so innervated. As with other antimuscarinic agents, the major action of atropine is a competitive or surmountable antagonism which can be overcome by increasing the concentration of acetylcholine at receptor sites of the effector organ (e.g., by using anticholinesterase agents which inhibit the enzymatic destruction of acetylcholine). The receptors antagonized by atropine are the peripheral structures that are stimulated or inhibited by muscarine (i.e., exocrine glands and smooth and cardiac muscle). Responses to postganglionic cholinergic nerve stimulation also may be inhibited by atropine but this occurs less readily than with responses to injected (exogenous) choline esters.

Achoo!, LPN · Oct 1, 2005

I am taking a physiology class along with my nursing classes. I know, call me crazy! In phys class we have case studies we have to answer questions on. So I have a question.
Why are nausea, abdominal cramps, diarrhea, and excessive salivation all side effects of the an anticholinesterase drug taken to improve a muscle disorder? What is the benefit of administering atropine and the corticosteroid, prednisone?

Well relaxing the smooth uscles in the Gi tract and decreasing peristalsis could cause the nausea and cramps.

Would it be used as an antispasmodic??

Daytonite, BSN, RN · Oct 2, 2005

Cholinergic drugs are given to MG patients to increase smooth muscle activity. Recall that the smooth muscles are the ones over which we have no conscious control and which perform all those little functions that keep our bodies going while we get on with our lives. A little too much of them leads to hyperactivity of the smooth muscles. The results are the nausea, diarrhea, abdominal cramps, increased salivation and increased sweating--all the result of smooth muscle overactivity. The atropine would be used to counteract the side effects of the cholinergic drugs and slow down smooth muscle activity; it is classifed as an anticholinergic. And, so the cycle goes around as a balance is attempted to be reached between these two classifications of medications being given to MG patients. The corticosteroids and prednisone are often given because it has been found that they improve the patient's symptoms, a common reason for steroid use in the autoimmune diseases.

maskp4 · Oct 2, 2005

I am taking a physiology class along with my nursing classes. I know, call me crazy! In phys class we have case studies we have to answer questions on. So I have a question.
Why are nausea, abdominal cramps, diarrhea, and excessive salivation all side effects of the an anticholinesterase drug taken to improve a muscle disorder? What is the benefit of administering atropine and the corticosteroid, prednisone?

Thanks all! You guys are great!