Epilepsy is the most common chronic neurological disease of the brain. It affects about one in 111 dogs. It causes irregular and abnormal impulses of nerve cells, which manifest themselves in so-called epileptiform seizures. These seizures are often associated with loss of consciousness and muscle spasms, and can lead to uncontrolled movements, urination and defecation, and increased salivation. Affected animals may also show only muscle contractions or abnormal movements (for example, typical fly snatching without flies present). The frequency and intensity of seizures depends on the cause and varies greatly from individual to individual.
A distinction is made between the following types of seizure:
- Focal seizures: only certain parts of the body are affected
- Generalised seizures: the whole body is affected
- Cluster seizures: more than one seizure within 24 hours.
- Status epilepticus: seizure duration longer than 5 minutes
The epileptiform seizure is divided into 4 phases: The prodromal phase describes the time before the seizure. During this phase, a change in behaviour, such as restlessness, seeking closeness, etc., can often already be observed. The actual seizure begins with the aura . This phase is characterised by a stereotypical behaviour of the animals, which announces the coming seizure. Visible may be salivating, smacking and licking, pacing back and forth and other non-normal behaviour. The ictal phase describes the actual seizure. Many and different symptoms can occur. Often the seizure is accompanied by loss or clouding of consciousness, muscle contractions, defecation, urination and others. The postictal phase describes the state after the seizure. The animals are usually still disoriented and may be temporarily blind or have other sensory impairments. The duration of the individual phases varies greatly and can last from seconds to a few minutes to hours.
Epilepsy can be congenital or acquired. There are two main types: primary and secondary epilepsy. Primary epilepsy is most common in dogs. Since the exact cause is still unclear and no lesions on the brain can be detected, it is also called idiopathic epilepsy. A genetic component has been proven for some breeds (e.g. Border Collie, Golden Retriever) and is also suspected in other breeds. In about 80% of epileptics, however, the cause remains unknown. In secondary or acquired epilepsy, there are structural changes in the brain that can be visualised on MRI. It is therefore also called structural epilepsy. Reactive epilepsy (metabolic), in which epileptiform seizures occur due to organic diseases, must be distinguished from these two forms. The distinction is important because the therapy is completely different. Examples are weakness or fainting due to hypoglycaemia, syncope (loss of consciousness) due to cardiovascular problems and the associated reduced supply of oxygen to the brain, electrolyte imbalances due to certain metabolic diseases (e.g. Addison's disease), or seizures and dizziness due to liver vascular anomalies (hepatoencephalic syndrome).
The correct diagnosis is very important for the differentiation and also delimitation of epilepsy. The first step in finding the diagnosis is, in addition to the clinical history, the general and neurological examination. This serves to localise the lesion. Subsequently, blood tests and, depending on the case, further examinations and tests are carried out. The previous seizures should be documented in detail (videos and diaries are very helpful). Special further diagnostics, such as an MRI or CT, cerebrospinal fluid (CSF) examination or measurement of brain waves (EEG) may also be necessary.
The therapy is composed of different, interconnected approaches. The first step is medication. Depending on the cause, seizure intensity and frequency, previous illnesses and other components, the appropriate anticonvulsant medication is selected. The respective dose, administration and combination of the drugs play an important role. According to studies, only about one third of all epileptics respond well to antiepileptic drugs and in about 60 % of cases complete freedom from seizures cannot be achieved.
As a further step, feeding should therefore be checked and optimised if necessary. Nutrition is the second most important pillar of epilepsy management. Research into possible supplements, especially special fatty acids, has developed very positively in recent years. The use of medium-chain fatty acids (MCT oils) has yielded promising results (Law et al., 2015; Berk et al., 2019, 2020). However, especially in epileptic patients, the administration of dietary supplements should be discussed with the veterinarian to avoid drug interactions and undesirable side effects at all costs. A behavioural and environmental analysis as a third pillar can also be necessary and helpful if there is no improvement or even a deterioration despite previous therapy.
In addition to the classic epilepsy described above, there are also special forms that can be positively influenced by diet. These include in particular Lafora epilepsy, which typically occurs in beagles, dwarf greyhounds and bassets, and paroxysmal glutensensitive dyskinesia in border terriers.
The neuro-dietary consultation for dogs and cats with epilepsy is a special form of dietary consultation. We offer individual nutritional advice for dogs with epilepsy. We have also developed special food supplements for dogs with epilepsy. These can be successfully integrated as part of a neuro-dietary feeding plan and have been specially designed for home-prepared rations as well as when giving ready-made food.