Sodium valproate

Question 1

Category

Answer 1

Category 2

Maintained on a specific brand based on clinical judgement (seizure frequency, treatment history etc.)

Question 2

MoA

Answer 2

Weak inhibitor of neuronal sodium channels.
Stabilises resting membrane potential.
Reduces neuronal excitability.

Question 3

Main risk

Answer 3

Highly teratogenic

Question 4

What type of seizures is valproate used for?

Answer 4

1st line in all types of generalised seizures.

Question 5

Sodium valproate + pregnancy

Answer 5

MHRA drug safety update 2018:
Valproate medicines (Epilim, Depakote) are contra-indicated in women and girls of childbearing age unless in Pregnancy Prevention Programme and only if there are no other alternatives.
Contraindicated in pregnant women for BPD and only considered in epilepsy if no alternative.

Question 6

Pregnancy Prevention Programme (PPP)

Answer 6

• For all women of child-bearing potential under specialist supervision when other treatments are not tolerated/effective
• ONE highly effective method of contraception (e.g. IUD or implant) or TWO complementary forms of contraception
  including a barrier method.
• Fully informed of the risks of use in pregnancy, and a signed risk acknowledgement form.
• Seen annually by specialist for review.

Question 7

PPP - Pharmacists role

Answer 7

• Provide valproate patient card.
• Remind pt. of risks in pregnancy/need for highly effective contraception.
• Remind of need for annual specialist review
• Dispense as whole pack - always give PIL
• Refer/contact GP if pt.not taking highly effective contraception.

Question 8

Side effects

Answer 8

• Hepatotoxicity
• Blood disorders
• Pancreatitis

Question 9

Hepatotoxicity

Answer 9

Potentially fatal
Discontinue if abnormally prolonged prothrombin time
Monitor LFTs
* Persistent vomiting
* Abdominal pain
* Jaundice
* Malaise
* Drowsiness

Question 10

Blood disorders

Answer 10

E.g. Leucopoenia, thrombocytopenia
Monitor - FBC
* Fever
* Sore throat
* Mouth ulcers
* Bruising or bleeding

Question 11

Pancreatitis

Answer 11

• Abdominal pain
• N + V

Question 12

Drugs that antagonise the anticonvulsant effect of sodium valproate

Answer 12

• Quinolone
• Mefloquine
• SSRIs
• Antipsychotics
• TCA/related antidepressants

Question 13

Drugs that increase the risk of hepatoxicity with sodium valproate

Answer 13

• Statins
• Carbamazepine
• Tetracyclines
• Fluconazole
• Isoniazid
• Itraconazole
• Methotrexate
• Sulfasalazine

Question 14

Sodium valproate increases the concentration of what drugs?

Answer 14

Enzyme inhibitors = increases the drug concentration of other anti-epileptic drugs e.g. lamotrigine, phenobarbital