Learning Outcomes
By the end of this section, you should be able to:
- 6.3.1 Identify drug–food interactions for their impact on treatments utilized for neurological disorders.
- 6.3.2 Identify treatments and medications that can cause nutritional deficiencies in clients with neurological disorders.
Specific dietary needs change over the course of a client’s lifespan, and certain neurologic conditions may benefit from a diet that contains specific key nutrients that promote health and delay symptoms. Anticonvulsants are medications used to prevent or treat epileptic seizures and can also cause nutritional deficiencies (Table 6.2). Clients who have experienced a stroke or who have Parkinson’s disease, myasthenia gravis, or ALS should be screened for dysphagia before offering oral meals and then must be monitored when eating for symptoms of choking, watery eyes, or coughing. While dysphagia symptoms among clients with ALS may present with slowly progressive symptoms that lead to a malnourished state, clients with Parkinson’s disease or myasthenia gravis may develop symptoms suddenly and may quickly develop exacerbations in which oral intake is not possible. The nurse should assess the client, perform a dysphagia screen, and withhold any oral intake until oral intake is safe. The risk for aspiration pneumonia can preclude oral feeding in clients with several neurologic conditions. If these symptoms are present, the nurse should consult with a speech pathologist and dietitian for the best treatment plan. Liquids may need to be thickened if dysphagia is present, and this can lead to dehydration. The nurse should follow fluid intake and urinary output closely to ensure adequate fluid status. In some cases, supplemental nutrition may be required temporarily or permanently via enteral feeding to ensure adequate nutrient and fluid intake.
| Medication | Nutritional Considerations |
|---|---|
| Anticonvulsant/Antiepileptic Medications (Alcohol should be avoided with all antiepileptic medications.) | |
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| Monoamine Oxidase Inhibitors | |
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| Tricyclic Antidepressants | |
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| Antipsychotic Drugs | |
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| Sleep Medications (Do not take with alcohol.) | |
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Drug–Food Interactions with Treatments for Neurological Disorders
Many clients with neurologic conditions require treatments and medications that can affect their nutritional status. It is important for the nurse to identify potential nutritional risks and help plan dietary adjustments with clients. This section familiarizes the nurse with some of the more common treatments and medications used for these clients.
A person’s genetic background strongly influences food and drug interactions, and certain nutritional deficiencies alter the gut microbiome, which can alter future medication absorption. Excessive intake of some vitamins can reduce the effectiveness of certain drugs, especially those used to treat epilepsy. Understanding the interactions between food and medications used for neurologic conditions among the health care team can ensure appropriate use and promote efficacy and client safety.
Nurses must consistently monitor clients for drug–food interactions; this is a collaborative effort involving the client reports, pharmacists, physicians, nurses, and dieticians. The ongoing assessment of clients receiving neurologic medications is critical. For example, identifying changes in body weight or nutritional deficits is key in promoting medication effectiveness and improving health (Table 6.3).
| Increased Body Weight | Decreased Body Weight |
|---|---|
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Antidepressants:
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Amphetamines:
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Neuroleptics:
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Antipsychotics:
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Benzodiazepines:
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Psychostimulants:
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Antiepileptics:
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Medications Used to Treat Parkinson’s Disease
One of the main medications used to treat Parkinson’s disease is levodopa, a dopaminergic agent. As the body metabolizes levodopa, elevated homocysteine levels (an amino acid) can present. This elevation can cause greater stiffness of the aorta and a lower bioavailability of CoQ10, placing the individual at a higher risk for cardiovascular events such as stroke. Therefore, due to the given the nature of the breakdown of levodopa, an adequate intake of folate, niacin, and vitamins B6 and B12 is recommended to prevent increased homocysteine levels, mitigating an increased cardiovascular risk. Alternatively, too much protein when taken with levodopa can inhibit its action, so medication should be taken 30–60 minutes before a meal and is not recommended in conjunction with a high-protein diet (Gezmen-Karadag, 2018). Sugar or fat can worsen Parkinson’s symptoms as these foods can inhibit absorption of levodopa, while a high-carbohydrate diet will increase the effect of levodopa (Gezmen-Karadag, 2018). In addition, clients with Parkinson’s disease who have a high levodopa requirement will often present with constipation and may require stool softeners.
Medications Used to Treat Epilepsy
Many of the anticonvulsant drugs (i.e., phenobarbital, carbamazepine) used to prevent seizures can also cause an increase in vitamin D metabolism in the liver and reduced bioavailability of vitamin D, which decreases calcium absorption in the intestine. This signals an increase in calcium uptake away from the bones. Low levels of vitamin D, serum calcium, and serum phosphate have been seen among children with epilepsy who receive these medications (Kija et al., 2019).
Other nutritional deficiencies that can result from taking antiepileptic drugs include low levels of biotin, an increase in homocysteine levels, and a deficiency of several B vitamins (Samahan et al., 2020). Therefore, it is recommended that clients taking anticonvulsant medications take calcium and vitamin D supplements. It was also noted that high folate levels can increase homocysteine concentrations and, therefore, folate levels should be monitored (Safahani et al., 2020). Hypocalcemia, reduced serum L-carnitine, zinc, and copper levels have been associated specifically with administration of phenytoin or valproic acid, but the supplementation of calcium has been shown to improve both cognition and function (Kija et al., 2019).
Nutrition education is recommended for clients prescribed valproic acid, as the intended action may be inhibited among people who consume large amounts of soy, as seen in vegan and vegetarian diets. Moreover, while some anticonvulsant medications, such as topiramate, may reduce total body weight, valproic acid has been associated with weight gain because of decreased serum glucose levels, which increase appetite. Clients who receive valproic acid should be closely monitored, as hepatotoxicity (injury to the liver or impaired liver function) may result. Clients taking any anticonvulsant medications should not consume alcohol, because these medications weaken the tolerance to alcohol, increasing the risk for intoxication. Table 6.4 provides a list of common medications used to treat seizures.
| Generic Name | Nutritional Effect |
|---|---|
| Carbamazepine |
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| Clonazepam |
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| Diazepam |
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| Ethosuximide |
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| Levetiracetam |
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| Midazolam |
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| Oxcarbazepine |
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| Phenobarbital |
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| Phenytoin |
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| Pregabalin |
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| Primidone |
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| Topiramate |
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| Valproic acid |
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Medications Used to Treat Multiple Sclerosis (MS)
Several medications and treatments may be used to treat clients with MS, depending on the type and severity of the condition and considering potential risks and benefits. One group of medications is immunomodulators. Interferon beta-1a is an injectable immunomodulator that is often prescribed to clients with MS, as it acts to reduce inflammation and halt nerve damage through the destruction of certain cells. While flu-like symptoms may be common, liver damage is a critical side effect of this medication. A loss of appetite as well as nausea, clay-colored stools, dark urine, and jaundice may indicate that the liver is failing and should be reported to the provider immediately (Filipi & Jack, 2020). One of the newest medications that prevent MS relapses is ofatumumab, which can also cause nausea, and if this occurs, the nurse should report it to the health care provider. A rare adverse and potentially lethal effect of this medication is brain infection, which could cause speech, vision, or muscle movement abnormalities. The ketogenic diet can reduce the need for medication in people with MS.
Medications Used to treat Depression, Psychosis, and Sleep
Several classes of medications are used routinely to treat depression, such as selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants, and monoamine oxidase inhibitors (MAOIs). One commonly prescribed medication to treat depression is fluoxetine, which may be associated with increased insulin levels and subsequent short-term weight gain in some individuals. Other common antidepressants, such as sertraline and paroxetine, have been linked to high LDL cholesterol, and long-term use may increase the risk for cardiovascular disease. Some of the tricyclic antidepressants, such as amitriptyline, may also cause weight gain, as they can increase appetite. A high intake of fiber foods, such as legumes, fish, and meat, and foods rich in vitamin C, may decrease absorption of these medications. Tyramine is a trace monoamine found in aged cheeses and cured meats and should be avoided if the client is taking a monoamine oxidase inhibitor. Some antipsychotic medications, such as chlorpromazine and clozapine, can cause a vitamin B12 deficiency and/or constipation. Therefore, supplemental B vitamins and minerals are recommended, as well as adequate fluid and fiber intake.
For clients with sleep disturbances, medications like zolpidem rapidly decelerate brain activity and can help them fall asleep and asleep. Clients taking sleeping medications should avoid caffeine and alcohol and should take them on an empty stomach to ensure adequate absorption. Zolpidem interacts with St. John’s wort, and the two should not be administered together. Another medication prescribed to treat insomnia, triazolam, should not be taken with grapefruit juice, as this has been shown to increase blood levels of the drug, causing excessive drowsiness.