Signs and symptoms
Symptoms of cardiomyopathies may include fatigue, swelling of the lower extremities and shortness of breath after exertion. Additional symptoms of the condition may include arrhythmia, fainting, and dizziness. Causes
Cardiomyopathies can be of genetic (familial) or non-genetic (acquired) origin. Genetic cardiomyopathies usually are caused by sarcomere or cytoskeletal diseases, neuromuscular disorders, inborn errors of metabolism, malformation syndromes and sometimes are unidentified. Non-genetic cardiomyopathies can have a definitive causes such as viral infections, myocarditis and others.Cardiomyopathies are either confined to the heart or are part of a generalized systemic disorder, both often leading to cardiovascular death or progressive heart failure-related disability. Other diseases that cause heart muscle dysfunction are excluded, such as coronary artery disease, hypertension, or abnormalities of the heart valves. Often, the underlying cause remains unknown, but in many cases the cause may be identifiable. Alcoholism, for example, has been identified as a cause of dilated cardiomyopathy, as has drug toxicity, and certain infections (including Hepatitis C). Untreated celiac disease can cause cardiomyopathies, which can completely reverse with a timely diagnosis. In addition to acquired causes, molecular biology and genetics have given rise to the recognition of various genetic causes.A more clinical categorization of cardiomyopathy as hypertrophied, dilated, or restrictive, has become difficult to maintain because some of the conditions could fulfill more than one of those three categories at any particular stage of their development.
On September 29, 2011, the FDA issued new guidance with regard to the DESI category. This effectively disallowed any new DESI formulations to enter the market. The FDA also has stated that DESI drugs do not have any therapeutic equivalent drugs listed in the “Orange Book”. In their description of therapeutic equivalence, the FDA specifically cites Donnatal®. Therefore, any so-called generic drugs on the market with similar formulation to DESI drugs, are considered illegal drugs as the FDA has not reviewed their composition or therapeutic equivalence. Donnatal, although containing phenobarbital, is exempt from the Controlled Substances Act due to the belladonna alkaloids present in the formulation. References
External links
"Donnatal Extended Release Tablet Information". Archived from the original on 2008-12-27.