Transient Ischemic Attack (TIA) or Minor Stroke: A brief episode of drooling and slurred speech could be indicative of a TIA or a minor stroke, including a lacunar stroke, which affects small blood vessels in the brain. The symptoms' transient nature fits the profile of a TIA, which is often a precursor to a more significant stroke.

Bell's Palsy: This condition causes temporary weakness or paralysis of the muscles in one side of the face, which could lead to drooling and slurred speech due to the inability to control facial muscles properly.
Migraine with Aura: Some migraines are accompanied by neurological symptoms (aura) that can include speech disturbances and potentially could lead to symptoms like drooling if the aura affects motor control.
Medication Side Effects: Certain medications, especially those with anticholinergic properties, can cause dry mouth, but others might lead to increased salivation or neurological side effects that could mimic the described symptoms.

Brain Hemorrhage or Large Vessel Stroke: Although less likely given the transient and mild nature of the symptoms, it's crucial not to miss a brain hemorrhage or a large vessel stroke, as these are medical emergencies requiring immediate intervention.
Infections like Meningitis or Encephalitis: Infections affecting the brain can present with a wide range of neurological symptoms, including speech changes and potentially drooling, especially if there's involvement of the brainstem or cranial nerves.
Seizure Activity: Certain types of seizures, especially those involving the frontal lobe, can cause transient neurological deficits, including speech disturbances and possibly drooling.

Multiple Sclerosis (MS) or Acute Disseminated Encephalomyelitis (ADEM): These demyelinating diseases can present with a wide array of neurological symptoms, including speech difficulties and potentially drooling, though this would be less common as an initial presentation.
Neurodegenerative Diseases (e.g., Parkinson's Disease, Amyotrophic Lateral Sclerosis): While these conditions typically have a more gradual onset, rare cases might present with sudden or transient symptoms that could be mistaken for a stroke or TIA.
Mitochondrial Disorders: Certain mitochondrial myopathies can have neurological manifestations, including stroke-like episodes, though these would typically be accompanied by other systemic or muscular symptoms.