Difficulty breathing, or dyspnea, can be mild to severe and is a common symptom of many diseases. Medical conditions associated with dyspnea include pneumonia, asthma, chronic obstructive pulmonary disease and heart failure. Additional testing including pulmonary function test, blood cultures and a chest x-ray can be used to diagnose causes of dyspnea. Certain medications can also cause dyspnea or exacerbate the underlying condition that is making the symptoms worse.
Amiodarone
Amiodarone is an antiarrhythmic medication used to treat irregular heart rhythms such as atrial fibrillation. Pulmonary toxicity occurs in approximately two percent of people who take amiodarone, and can develop regardless of dose or duration of therapy. Those with a history of lung problems are at higher risk. Symptoms include unexplained dyspnea and cough. A baseline chest x-ray and pulmonary function test is required before starting amiodarone and should be repeated if unexplained dyspnea and cough develop. Discontinuation of amiodarone is often necessary.
Opioid Analgesics
Morphine is the base for which all other opiod analgesics, such as codeine and hydrocodone, are derived from. Opioid analgesics are used to treat severe pain and primarily affect the central nervous system. Breathing problems develop because opioids interfere with respiratory messages from the brain. Severe cases can lead to respiratory depression and possibly death. An opioid antagonist is given in cases where the patient becomes unresponsive. This is a dose-related side effect of opoid analgesics and people taking these medications should be monitored closely.
Beta-blockers
Beta-blockers, such as atenolol and metorpolol, are commonly used in people with high blood pressure, coronary artery disease and heart failure. These medications work primarily in the cardiovascular system, but also have affects on the respiratory system. Beta blockage in the lungs can lead to airway resistance, making it difficult to breathe. This is particularly problematic in people with asthma, which explains why these drugs should be avoided in this population. Although some beta-blockers are more specific to affect only the cardiovascular system, no beta-blocker is completely safe in patients with severe, underlying respiratory illnesses.
References
- "Basic and Clinical Pharmacology"; Bertram G. Katzung; 2004
- "Heart Rhythm"; A Practical Guide for Clinicians Who Treat Patients with Amiodarone: 2007; Nora Goldschlager, et al.; 2007
