Sodium valporate Flashcards
1
Q
What is the method of action of sodium valporate?
A
- Not fully understood
- Weak inhibitor of neuronal sodium channels
- = stabilising membrane potentials
- = ↓ neuronal excitability
- Also ↑brain content of GABA which regulates neuronal inhibition
2
Q
What are the indications for sodium valporate?
A
- Epilepsy – 1st line for control of generalised/absence seizures, treatment for focal seizures
- Bipolar disorder – acute treatment of manic episodes and prophylaxis
3
Q
What are the contraindications for sodium valporate?
A
- Woman of child bearing age
- Conception
- 1st trimester of pregnancy – neural tube defects, developmental delay, craniofacial, cardiac and limb abnormalities
- Hepatic impairment
- Severe renal impairment
4
Q
What are the side effects of sodium valporate?
A
- GI upset
- Tremor
- Ataxia
- Behavioural disturbances
- Thrombocytopenia
- ↑ liver enzymes
- Hair loss – with hairgrowth curlier
- Severe liver disease
- Pancreatitis
- Bone marrow failure
- Antiepileptic hypersensitivity syndrome
5
Q
What drugs does sodium valporate interact with?
A
- Warfarin - ↑ conc. in this drug in the system
- Other antiepileptic drugs - ↑ conc. in this drug in the system
- Carbapenems – valproate conc. ↓
- Macrolides – valproate conc. ↑
- Protease inhibitors – valproate conc. ↑
- Aspirin – drug displaces it from the protein binding sites
- SSRIs - ↓ seizure threshold
- Tricyclic antidepressants - ↓ seizure threshold
- Antipsychotics - ↓ seizure threshold
- Tramadol - ↓ seizure threshold
6
Q
What information should a patient taking sodium valporate be given?
A
- Take tablets with food to reduce tummy upset
- Look for lethargy, loss of appetite, vomiting, abdominal pain (liver poisoning) or bruising, high temp or mouth ulcers (blood abnormalities)
- Woman – discuss contraception and pregnancy
- Do not drive unless seizure free for 12 months (or asleep only seizures over 3 years) and for 6 months after changing/stopping treatment
