Exam 3 lecture 8 Flashcards
What is antiseizure drug withdrawal syndrome
Associated with abrupt discontinuation of antiseizure medication therapy.
may cause a recurrence of seizures, doses should always be tapered for discontinuation.
Antiseizure drugs that are controlled substances may have physiological and psychological dependence associated with them.
abrupt discontinuation can cause additional symptoms such as anxiety, agitation, physical complaints
What happens to Vd in pregnancy?
Which drugs should not be used in pregnancy?
Supplements?
What should infants receive?
Vd changes in pregnancy
Many antiseizure drugs are known teratogens. Carbamezapine, clonazepam, fosphenytoin, phenobarbital, phenytoin, primidone, topiramate. Counsel for people of child bearing age to use contraceptives.
Valproate is also not recommended as it has neural tube effects associated with it. Also a decrease in IQ of child associated with it.
Supplemental folic acid should be consodered in pregnancy.
Infant child should receive 1 mg IM vit K to reduce risk of hemorrhagic disease
What are contraceptive drug interactions mediated by?
How to manage these drug interactions?
How does estrogen affect lamotrigine and vice versa?
Mediated by CYP 3A4 induction. Estrogen cpds are mahor 3A4 substrates.
These interactions can be managed by using a higher dose of estrogen contraceptives.. Warning for increased thromboembolism. Can use progestin (depot or IUD)
estrogen can reduce lamotrigine serum concentration and lamotrigine can reduce estrogen concentration.
Cardiovascular adverse effects associated with each anticonvulsant drug
Arrhythmia- lamotrigine, phenytoin, phosphenytoin
PR interval changes- Lacosamide, pregabalin
Heart block- lacosamide
Vascular heart disease- fenfluramine
Which anticonvulsant drugs are associated with syndrome of inappropriate antidiuretic hormone (SIADH)
Carbamezapine, eslicarbazapine, oxcarbamezapine,
Which anticonvulsant drugs alter vit D metabolism? What does this cause?
Phenytoin. Causes reduced calcium concentration, leading to OP with long term use.
Which anticonvulsant drug leads to metabolic acidosis? What to monitor? What does this cause
Topiramate
monitor serum bicarbonate (is also a CAI)
associated with reduced sweating, heat tolerance and oligohydrosis
psychiatric side effects of levetiracetam
Psychosis, suicidal thoughts/behaviors, unusual mood changes, worsening of depression
Perampanel boxed warning
Dose related serious and/or life threatening neuropsychiatric events (use with caution in pre existing psychosis)
psychiatric side effects of valproate
acute mental status changes related to hyper ammonemia
psychiatric side effects of topiramate
Associated with cognitive dysfunction if dose is increased too rapidly. Use slow dose titration
Which antuconvulsant drugs cause visual abnormalities
Topiramate
vigabatrin
What are risk factors to look out for when considering gabapentin or pregabalin for treatment
Risk for respiratory depression in pt who is taking other CNS depressants, has pulmonary disease or is elderly
Which anticonvulsant drugs cause hyponatremia
Carbamezapine, oxcarbamezapine, esilcarbamezapine
Which anticonvulsant drug causes thrombocytopenia? What to minitor? What can it cause in pt who are taking this drug
Valproate
Monitor CBC/platelets
can cause PCOS, weight gain, sedation
What does carbamezapine induce? Oxcarbamezapine?
Carbamezapine- strong 1A2, 2C9, 2C19, 3A4 and p-glycoprotein inducer
oxcarbamezapine- 3A4
Topiramate and zonisamide what do they cause?
Weight loss, oligohydrosis, nephrolithiasis
What can phenytoin cause?
Gingival hyperplasia and hirsutism
What decreases phenytoin absorption in body
Food. take 1-2 hours before and after feeding