Drug Interactions between benzgalantamine and dexamethasone / ketorolac / moxifloxacin

Moxifloxacin and other medications in its class can cause tendinitis and tendon rupture, and the risk may be increased when combined with a steroid such as dexAMETHasone. Older adults over 60 years of age and those who have received a kidney, heart, and/or lung transplant may be particularly susceptible. Tendon rupture can occur during or up to several months after finishing moxifloxacin treatment and may require surgery or result in prolonged disability. Talk to your doctor if you have any questions or concerns. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring to safely use both medications. Stop taking moxifloxacin and call your doctor immediately if you experience pain, swelling, or inflammation of a tendon area such as the back of the ankle, shoulder, biceps, hand, or thumb. You should also avoid exercise or use of the affected area until further instruction from your doctor. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Using dexAMETHasone together with ketorolac may increase the risk of side effects in the gastrointestinal tract such as inflammation, bleeding, ulceration, and rarely, perforation. Gastrointestinal perforation is a potentially fatal condition and medical emergency where a hole forms all the way through the stomach or intestine. You should take these medications with food to lessen the risk. Talk to your doctor if you have any questions or concerns. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring to safely use both medications. Your doctor may also be able to recommend medications to help protect the stomach and intestine if you are at high risk for developing serious gastrointestinal complications. You should seek immediate medical attention if you experience any unusual bleeding or bruising, or have other signs and symptoms of bleeding such as dizziness; lightheadedness; red or black, tarry stools; coughing up or vomiting fresh or dried blood that looks like coffee grounds; severe headache; and weakness. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Consumer information for this interaction is not currently available.

MONITOR: Concomitant use of acetylcholinesterase inhibitors and corticosteroids or adrenocorticotropic agents may result in severe muscle weakness in patients with myasthenia gravis. The mechanism of the interaction is unknown. It has been suggested that corticosteroids at high doses have a direct effect on neuromuscular transmission. Marked deterioration in muscle strength has been reported in patients with myasthenia gravis shortly after the initiation of corticosteroid therapy, particularly when high dosages were used. The use of cortisone appears to be associated with the highest rate of myasthenia gravis exacerbation, with an intermediate rate for prednisone and the lowest rate for methylprednisolone. In most cases, the decline in muscular function was relatively refractory to acetylcholinesterase inhibitors. However, clinical improvement generally occurs during prolonged corticosteroid therapy when administered properly.

MANAGEMENT: Caution and monitoring for muscle weakness is recommended with the use of corticosteroids or adrenocorticotropic agents in combination with acetylcholinesterase inhibitors in the treatment of patients with myasthenia gravis. Prednisone or prednisolone are often considered part of the standard treatment for this condition. Recommendations in the medical literature have advised that corticosteroid therapy should be instituted at relatively low dosages and in a controlled setting in patients with myasthenia gravis. Respiratory support should be available, and the dosage should be increased stepwise as tolerated. Dose reductions of the acetylcholinesterase inhibitor may be required as symptoms improve, which often may be delayed and gradual. However, according to some manufacturers of the corticosteroids dexamethasone and triamcinolone, anticholinesterase agents should be discontinued at least 24 hours before initiating corticosteroid therapy in patients with myasthenia gravis. Other management recommendations in the medical literature suggest avoiding the use of corticosteroids at high doses; however, if high doses are required, consider pre-treatment with intravenous immunoglobulin or plasmapheresis. Local protocols and/or the manufacturer's product labeling should be consulted for specific guidance.

Moxifloxacin may rarely cause central nervous system side effects such as tremors, involuntary muscle movements, anxiety, confusion, depression, hallucinations or seizures, and combining it with other medications that can also affect the central nervous system such as ketorolac may increase that risk. Talk to your doctor if you have any questions or concerns. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Consumer information for this interaction is not currently available.

MONITOR: The concomitant use of acetylcholinesterase inhibitors (ACHEIs) (e.g., donepezil, galantamine, benzgalantamine physostigmine, rivastigmine, tacrine) with nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk of gastrointestinal (GI) bleeding. ACHEIs can increase gastric acid secretion due to their cholinergic effects and NSAIDS may increase the risk of GI bleeding and ulceration. In a Swedish retrospective case study of 70,060 patients aged 65 years and older with new prescriptions for both ACHEIs and NSAIDs, 1500 persons were diagnosed with incident peptic ulcer. The results suggested that the risk of peptic ulcer was significantly increased for the combination of ACHEIs and NSAIDs compared to NSAIDs alone. No increased risks were found for the use of ACHEIs alone.


MANAGEMENT: Caution and clinical monitoring are recommended if concomitant use of ACHEIs and NSAIDs is required, especially in patients with a prior history of peptic ulcer disease, the elderly, or debilitated patients. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence gastrointestinal bleeding such as black or tarry stools, bright red blood in vomit, coffee ground like vomit, abdominal pain or cramping, diarrhea, dizziness or lightheadedness, weakness or fatigue and pale skin.

Consumer information for this interaction is not currently available.

MONITOR: Acetylcholinesterase inhibitors may have vagotonic effects on the sinoatrial and atrioventricular nodes, which occasionally manifest as bradycardia or heart block (<2%). Because bradycardia is a risk factor for torsade de pointes, a theoretical risk exists when combined with agents that prolong the QT interval. In general, the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable but may be increased by certain underlying risk factors including, but not limited to congenital long QT syndrome, cardiac disease, and electrolyte disturbances (e.g., hypokalemia, hypomagnesemia). In addition, the extent of drug-induced QT prolongation may vary depending on the dosage(s) and specific drug(s) involved.

MANAGEMENT: Caution is advised when acetylcholinesterase inhibitors are used with drugs that can prolong the QT interval. Patients should be monitored for bradycardia, atrioventricular block and syncope, and advised to seek medical attention if they experience dizziness, lightheadedness, fainting, shortness of breath, or slow or irregular heartbeat.