Sunday, January 8, 2017

Medication Madness: Continuous Famotidine/Pepcid Infusion (CFI)

Mast Cell Disease encompasses numerous conditions that impact the functioning and/or production of mast cells. To provide a brief synopsis, mast cells are a type of immune cell. They play a significant role in the defense against pathogens. [ x ] 

Mast cells release chemicals called mediators when triggered. The mediators cause a host of symptoms ranging from mild to life-threatening. Quite a few, but not all, are allergic in nature. 


Histamine (H1 + H2) blockers are a common treatment for Mast Cell Disease because histamine is one of the many chemical mediators released from mast cells. Diphenhydramine, the fancy term for Benadryl, is an H1 blocker. It comes in oral, intramuscular, and intravenous forms. In severe cases, the typical medication administration is ineffective. To reduce life-threatening symptoms, the severely afflicted patients sometimes resort to a continuous intravenous infusion of Diphenhydramine (Benadryl). 

Read Diphenhydra-What? Life On A Continuous Benadryl Pump to learn more about the Continuous Diphenhydramine Infusion (CDI).  

Similar to Diphenhydramine (Benadryl), Famotidine (Pepcid)n is also a histamine blocker. They just act on different receptors, making Famotidine (Pepcid) an H2 blocker. It is available in oral pill form or intravenous (IV). 

In February 2016, my doctors implemented the continuous infusion with Famotidine (Pepcid) too. The concept is even less common than continuous intravenous Diphenhydramine (Benadryl). While I do not receive the same baffled responses regarding the Pepcid like I do with the continuous Diphenhydramine (Benadryl), I am here to share the good, the bad, and the ugly about my continuous Famotidine infusion CFI experience. 

"What is it?"

The CFI is a continuous, 24 hour intravenous infusion of Famotidine (Pepcid). It is administered via pump into a central line. 

"How does it work?"

On a weekly basis, a home infusion company delivers weekly infusion and enteral (tube feeding) supplies. The CFI is included in the delivery. 

In a delivery, I receive a weeks worth of IV bags containing Famotidine (Pepcid) for the 24 hour infusion diluted in NS saline by the pharmacist at the home health pharmacy. Each bag is connected to a portable pump. 

"What is the dosing?"  

Before the intravenous medications, I took an H2 blocker tablet orally multiple times a day. I have been on Zantac, Pepcid, and Tagament over the years. Unfortunately, disease progression led to taking typical administration of intravenous dosing of 40 to 60 mg of Famotidine (Pepcid) per 8 to 12 hours. Both of these methods failed to optimally control symptoms. During a MASSIVE flare, the doctor suggested to cease regular IV dosing and prescribed the CFI.

The prescription read as follows: 60 mg Famotidine/Pepcid diluted in 300 mL NS (saline) to infuse at 12.5 mL/hr to equal 2.5 mg/hr.

"What symptoms does it prevent?" 

The benefits of the continuous Famotidine (Pepcid) are not as vast as the continuous Diphenhydramine (Benadryl). However, the continuous H2 blocker like Famotidine (Pepcid) is still helpful. There are H2 receptors in the gut and on the skin. So, the majority of the symptom relief from Famotidine are in those areas. 

There were evident improvements from the CFI in:

  • Skin -  flushing, itching, rashes
Skin manifestations decreased 90%
  • GERD - reflux, heartburn, gastric pain
  • Breathing - dry cough

The coverage of regular IV dosing of Famotidine (Pepcid) is not nearly as good as the CFI administration, as it does not yield sustained results. Symptoms significantly increase before the next dose is due. The continuous infusion leaves little room for breakthrough symptoms because there is a 
small amount of the medication constantly in the system. 

"Do you get any side effects?" 

This is where it gets tricky.  The CFI is not a "normal" treatment, especially for long term with a Mast Cell Disease. Long term effects are unknown. I began the CFI February 2016 and stopped it October 2016. Initially, it helped immensely! 

Never did I experience side effects from the drug itself. By June 2016, unbeknownst to us, the Famotidine began to trigger my mast cells. An exhausting aspect of Mast Cell Disease is that anything can become a trigger, even medications designed to improve the disease. What is safe one moment can kill in the next. 

The prominent symptoms it caused, while also serving as a mast cell trigger, are listed below. Each are common when my Mast Cell Disease flares. They were present to varying extents prior to the CFI and not a direct result of the drug itself.

  • Swelling
  • Pancreatitis
  • Mild Dystonia
  • Increased Pain (i.e. bone pain, burning sensation, skin pain, general ache of organs)
  • Cessation of Menstrual Period (unrelated to low weight)
  • Unexplained weight loss
  • Erratic Blood Sugar Levels (i.e. reactive hypoglycemia)
  • Neuropathy
  • Inability to Stand (i.e. stress on body from standing triggers anaphylaxis, became 99% wheelchair bound)

There was much experimentation involved to find an ideal solution. The CFI was decreased from an overall total of 60 mg Famotidine (Pepcid) daily to 40 mg daily with no resolution. Next, I restarted regular bolus dosing. 20 mg per 8 hours was given, then 20 mg twice daily, then I ceased to take it at all. That did not work either.

Thankfully, we found what is working for me currently: 

I am not longer on the CDI, but one 20 mg dose of Famotidine (Pepcid) in 24 hours. My cells were less than pleased to have a "trigger" infusing every second of the day. The medication worsened things once I began reacting to it, but simultaneously helped some symptoms too. 

The improvements of stopping the CFI outweigh the symptoms it benefited once Famotidine (Pepcid) began serving as a trigger. Since the mentioned symptoms are from the disease, they are intermittent depending on triggers. They did not all necessarily go away after stopping the CFI. There are drastic improvements though. Pain has decreased significantly. My weight is slowly increasing (80 lbs to 88 lbs). The chronic pancreatitis is not flaring as badly. Where I ended up 99% wheelchair bound, I am now able to walk short distances around the house without complete mast cell chaos. 

Verdict?

The CFI definitely has its advantages. It is a fantastic short term option best reserved for massive flares. Long term exposure can increase the possibility of mast cells revolting against a medication designed to help, which is reflected through my experience.