Benign Fasciculations: This condition is characterized by involuntary muscle twitches that can occur at any time, including at night. It is often benign and can be related to fatigue, stress, or excessive caffeine intake.

Restless Leg Syndrome (RLS): Although primarily associated with an urge to move the legs, RLS can sometimes manifest as muscle jerks or twitches, especially in the evening or at night.
Periodic Limb Movement Disorder (PLMD): Similar to RLS, PLMD involves involuntary movements of the limbs during sleep, which can be perceived as muscle jerks.
Hypnic Jerks: These are sudden, brief contractions of the muscles that occur when falling asleep, often accompanied by a sense of falling or shock.

Amyotrophic Lateral Sclerosis (ALS): While less common, ALS can initially present with fasciculations (muscle twitches) that may be more noticeable at night. Early diagnosis is crucial for management.
Neuropathy: Certain neuropathies, especially those affecting the peripheral nerves, can cause muscle weakness, pain, and twitching, which might be more pronounced at night.
Magnesium Deficiency: A significant deficiency in magnesium can lead to muscle cramps, spasms, and twitches, which could occur nocturnally.

Isaac's Syndrome (Neuromyotonia): A rare condition characterized by continuous muscle activity leading to stiffness, cramps, and delayed relaxation of the muscles after contraction.
Cramp-Fasciculation Syndrome: A rare disorder that presents with muscle cramps and fasciculations, potentially related to a channelopathy affecting muscle and nerve function.
Thyroid Disorders: Both hyperthyroidism and hypothyroidism can lead to muscle symptoms, including twitches and cramps, though these are less commonly the primary presenting symptom.