Neuro Drugs Flashcards
Anti-convulsant names
lamotrigine, perampanel, phenobarbital and phenytoin
When are anti-convulsants(lamotrigine, phenytoin) used
Epileptic seizures prevention
Anti-convulsants side effects
Induce hepatic enzymes - make COCP, POP, implants etc not effective
Cholinesterase inhibitors names
donepezil, rivastigmine (DLB, DPD), galantamine
When are Cholinesterase inhibitors used
- Slow cognitive decline for some forms of dementia
- More effect in DLB/DPD than Alzheimers
Contraindications to - Cholinesterase inhibitors
May worsen COPD/asthma
Cholinesterase inhibitors side effects
- GI (nausea and diarrhoea most common)
- Headache
- Muscle cramps
- Bradycardias
Memantine mech of action
NMDA receptor antagonist
When to use Memantine
Used in moderate or severe AD or where cholinesterase inhibitors are not tolerated - slow cognitive decline and prevents BPSD
Contraindications to memantine
May cause hypertension
Memantine side effects
- Hypertension
- Sedation
- Dizziness
- Headache
- Constipation
Opioid mech of action
Act on G-protein-coupled opioid receptors, μ is responsible for most of the analgesic action of opioids
Opioid contraindications
Caution - opioid dependence/addiction
Opioid side effects
- Apnoea
- Orthostatic hypotension
- Nausea, vomiting, constipation, increased intrabillary pressure
Name some opioid receptor antagonists
- Naloxone - used to reverse opioid toxicity
- Naltrexone - similar to naloxone
- Alvimopan, methylnaltrexone - do not enter CNS, reduce G.I. effects of surgical and chronic opioid agonist use
NSAID mech of action
Inhibiting the synthesis and accumulation of prostaglandins by cyclo-oxygenase (COX) enzymes COX-1 and COX-2
Contraindications to NSAIDs
- Contraindicated in active GI bleeding/ulceration, patients with a history of GI bleeding/perforation related to previous NSAID therapy, and in patients with a history of recurrent GI ulceration
- Also avoid long term NSAIDs in patients with ischaemic heart disease
NSAIDs side effects
Long term administration of non-selective NSAIDs may produce gastrointestinal damage (PGE2 produced by COX-1 protects against the acid/pepsin environment)
When to use Gabapentin and pregabalin
- Antiepileptics but used in the treatment of chronic pain
- Gabapentin is employed in migraine prophylaxis
- Pregabalin is useful in painful diabetic neuropathy
Gabapentin and pregabalin mech of action
- Reduce the cell surface expression of a subunit (α2δ) of some voltage-gated Ca2+ channels (high-voltage-activated subgroup) which are upregulated in damaged sensory neurones
- This presumably causes a decrease of neurotransmitters, such as glutamate and substance P, from the central terminals of nociceptive neurones
Gabapentin and pregabalin contraindications
Can’t use in preg
When to use Carbamazepine
First-line treatment to control pain intensity and frequency of attacks in trigeminal neuralgia
Carbamazepine mech of action
Blocks subtypes of voltage-activated Na+ channels that are upregulated in damaged nerve cells
Carbamazepine side effects
P450 enzyme inducer
Diplopia
Leucopenia
Hyponatraemia
Headache
Drowsiness
Dizziness
Ataxia
Stevens-Johnson syndrome
