The symptoms of MS rarely look the way they do in medical textbooks. Fatigue is not sleepiness. Cognitive fog is not forgetfulness. Spasticity is not a cramp. These terms give names to experiences that can otherwise feel isolating or hard to describe, and many of them come directly from the MS community rather than from clinicians. Having the right word can make conversations with family, employers, and care teams more precise.
8 terms in this topic
Fatigue
MS fatigue is a deep, heavy tiredness that is different from being sleepy or out of shape. It can show up even after a full night of rest and can make ordinary tasks feel much hard...
Cognitive Fog
Cognitive fog, sometimes called brain fog or cog fog, describes trouble with thinking clearly. It can include slower processing, losing your train of thought, struggling to find wo...
Spasticity
Spasticity is unusual stiffness or tightness in muscles, often in the legs. It can feel like a muscle that will not relax, a sudden jerk, or resistance when you try to move. It can...
Foot Drop
Foot drop is trouble lifting the front of the foot while walking, which can cause the toes to drag or catch. It happens when the nerves that control the muscles in the lower leg ar...
Paresthesia
Paresthesia is the medical word for feelings like numbness, tingling, pins and needles, or a buzzing sensation in the skin. In MS, it can show up in a hand, a foot, an arm, or a ba...
Heat Sensitivity
Heat sensitivity is the tendency for MS symptoms to get worse when your body temperature rises. Warm weather, hot showers, fevers, and intense exercise can all trigger it. Cooling ...
Uhthoff's Phenomenon
Uhthoff's phenomenon is when MS symptoms temporarily get worse as your body heats up. Triggers can include hot weather, a hot shower, exercise, or a fever. Symptoms usually settle ...
Spoon Theory
Spoon theory is a way to talk about limited energy when you have a chronic illness. The idea is that you start each day with a set number of spoons, and every task, from getting dr...
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Reviewed by the MS Buddy editorial team. Not medical advice — always consult your care team.