Hypothyroidism: This condition is a common cause of generalized weakness and can also lead to tremors. The metabolic slowdown associated with hypothyroidism can affect muscle strength and nervous system function, leading to these symptoms.

Vitamin B12 Deficiency: A deficiency in vitamin B12 can cause generalized weakness, tremors, and other neurological symptoms due to its crucial role in the synthesis of myelin and the maintenance of the nervous system.
Diabetes Mellitus: High blood sugar levels can lead to generalized weakness and tremors, among other symptoms, due to the osmotic effects of glucose on nerve and muscle cells.
Anxiety or Stress: Prolonged periods of anxiety or stress can manifest physically as generalized weakness and tremors due to the body's 'fight or flight' response and the subsequent hormonal changes.
Medication Side Effects: Certain medications, such as beta-blockers, anticonvulsants, and some antidepressants, can cause tremors and weakness as side effects.

Parkinson's Disease: Although less common, Parkinson's disease is a critical diagnosis not to miss. Early symptoms can include tremors, weakness, and rigidity, making it essential to consider in the differential diagnosis.
Multiple Sclerosis: This autoimmune disease can cause a wide range of neurological symptoms, including weakness and tremors, due to the damage it inflicts on the central nervous system.
Stroke or Transient Ischemic Attack (TIA): While typically presenting with more focal neurological deficits, in some cases, generalized weakness and tremors could be symptoms of a stroke or TIA, especially if the brainstem is involved.
Hyperthyroidism: Similar to hypothyroidism, an overactive thyroid gland can cause tremors and generalized weakness due to the accelerated metabolic rate affecting muscle and nerve function.

Wilson's Disease: A genetic disorder leading to copper accumulation in the body, which can cause neurological symptoms including tremors and weakness.
Friedreich's Ataxia: A rare genetic disease causing progressive damage to the nervous system, resulting in symptoms such as weakness, tremors, and ataxia.
Mitochondrial Myopathies: A group of disorders affecting the mitochondria, leading to muscle weakness and other systemic symptoms, including tremors in some cases.
Neurodegenerative Diseases (e.g., Huntington's Disease, Spinocerebellar Ataxias): These conditions can present with a variety of neurological symptoms, including generalized weakness and tremors, although they are less common.