Apple (seeds)

Symptoms reported in cats

Most serious first.

1. 1
   Difficulty Breathing and Hyperventilation Rapid onset (often within minutes to a few hours). · The hydrogen cyanide released from crushed apple seeds binds to enzymes in the cells, completely halting cellular oxygen metabolism12. This tissue suffocation forces the cat to hyperventilate and gasp for air as the body attempts to compensate.
2. 2
   Muscle Tremors, Incoordination, and Seizures Rapid onset. · Because the brain has incredibly high oxygen and energy demands, the sudden halt in cellular ATP (energy) production caused by the cyanide rapidly deprives the brain of power, leading to profound neurological distress.
3. 3
   Coma and Cardiac Arrest Rapidly following respiratory distress and seizures. · As the cyanide completely halts cellular respiration, the resulting rapid cellular death in the vital high-oxygen-demand organs (the brain and heart) leads to cardiovascular collapse, loss of consciousness, and ultimately death if untreated.
4. 4
   Cherry-Red Mucous Membranes Rapid onset. · Because cyanide blocks the body's cells from extracting and taking up oxygen from the bloodstream, venous blood remains fully saturated with oxygen. This causes a distinct, abnormally bright red coloration of the cat's skin, gums, and mucous membranes.
5. 5
   Vomiting and Diarrhea Shortly after ingestion (often within 30 minutes to a few hours). · These gastrointestinal signs are frequently the first early symptoms of acute cyanide toxicity after a cat ingests and metabolizes toxic seeds.

Important notes

Apples are widely consumed fleshy fruits that contain a central core housing several seeds (often referred to as pips or kernels). Like other plants in the Rosaceae family, the seeds of the apple naturally contain cyanogenic glycosides, specifically a compound known as amygdalin (HCN).