Drug Interactions between donepezil and moxifloxacin / triamcinolone

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 triamcinolone. 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.

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.

Donepezil can occasionally cause slowing of the heart rate or other irregular heart rhythm, and combining it with medications like moxifloxacin 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 to safely use both medications. Contact your doctor if you develop dizziness, lightheadedness, fainting, shortness of breath, chest pain, or heart palpitations during treatment. 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.