BB Drugs Flashcards
Alcohol - what types of tolerance can occur?
Acute
Cellular
Even pharmacokinetic (in severe alcoholism)
Where areas of the brain does alcohol work on?
Frontal cortex (hypnotic effects) Reticular formation (disinhibits behaviour)
What channel does alcohol work on?
It reduces the activity of voltage-gated calcium channels, reducing neurotransmitter release
What are the kinetics of alcohol?
Zero order
What are the physical withdrawal symptoms (alcohol)?
Agitation, anxiety, sweating, delirium tremens, convulsions
Explain pharmacokinetic tolerance with alcohol?
At high levels of chronic consumption, alcohol can increase the activity of cytochrome P450 group of oxidative liver enzymes.
Amantadine - what disease is it used to treat?
Parkinson’s
How does amantadine work?
Inhibits dopamine reuptake and increases dopamine release
What class of drug is amitriptyline?
Tricyclic antidepressant
What can amitriptyline be used to treat?
Huntington’s, depression, neuropathic pain, cancer pain
How does amitriptyline work?
Inhibits reuptake of amines, as well as blocks sodium and calcium channels
It potentiates monoaminergic transmission
What are the side effects of amitriptyline?
Dry mouth, blurred vision, constipation, urinary retention, aggravation of narrow angle glaucoma, fatigue, sedation, weight gain, postural hypotension, dizziness, loss of libido, arrhythmias
Dangerous in overdose (cardiotoxicity)
What receptors does amitriptyline (and other TCAs) have affinity for?
5-HT, H1, muscarinic, alpha-1 and 2 adrenoceptors
Amphetamine (speed) - how does it exert its effects?
Indirectly acting sympathomimetrics - acts to potentiate the effects of catecholamines by stimulating release
Inhibits reuptake
Inhibits MAO activity
What are the effects of amphetamine?
Suppresses appetite
Hallucinations
High blood pressure
Psychosis (?)
Where in the brain does amphetamine act?
Nucleus accumbens, hypothalamus and reticular formation
What type of dependence occurs with amphetamine?
What type of tolerance?
Only psychological
Cellular
What is aripiprazole?
Atypical anti-psychotic
How does aripiprazole work?
D2 receptor antagonist
Also 5-HT2 receptor
PARTIAL AGONIST
What is one of the benefits of atypical vs typical anti-psychotic drugs?
They improve cognition
What is aspirin/how does it work?
NSAID - COX-1 and 2 inhibitor
Analgesic, anti-pyretic, anti-inflammatory
What is baclofen used for?
Pain for trigeminal neuralgia, symptomatic treatment of MS (anti-spastic, causing sedation and muscle weakness)
What receptor does baclofen work at?
GABA B agonist
What is benserazide?
Peripherally acting DOPA decarboxylase inhibitor
What are some of the uses of benzodiazepines?
Anti-spastics for MS. ANXIOLYTICS SEDATIVES HYPNOTICS ANTICONVULSANTS - epilepsy
What are the negatives of using benzodiazepines?
Can cause sedation and are addictive.
What is clonazepam used for?
Myoclonic seizures
What is IV diazepam used for?
Status epilepticus
What are the withdrawal effects of BZD
Convulsions, panic attacks and anxiety.
What receptor do BZDs work on?
Positive allosteric GABA A modulator – they bind and cause a transient conformational change of the receptor, which increases the activity of the ion channel. Increases the frequency of channel opening events in the presence of GABA, which leads to an increase in chloride ion conductance and inhibition of the action potential.
What areas of the brain do BZD work on?
Raphe nuclei (anxiolytic) and reticular formation (sedation).
Benztropine - what is it used for?
Anti-cholinergic agent used in PD - resting tremor responds most to this medication.
Benztropine – what are the side effects?
Dry mouth, cough, constipation, blurred vision and confusion.
Buspirone - how does it work?
5-HT 1A agonist (activate this receptor to reduce 5-HT transmission). 5-HT1A receptors are inhibitory somatodendritic receptors, so agonists initially REDUCE release of 5-HT. Long-term treatment desensitizes 5-HT1A autoreceptors, so results in an INCREASED RELEASE of 5-HT and potentiation of transmission.
What is buspirone used for?
Anxiety
How long does buspirone take to work?
Two weeks (the effects involve a slow process of change in the receptors) .
Caffeine - how does this work?
Adenosine (A1 receptor) antagonist and it inhibits phosphodiesterase, both leading to an increase in c-AMP. This potentiates catecholamines in the brain.
What areas of the brain does caffeine work on?
Nucleus accumbens and reticular formation
What type of dependence is there with cannabis?
Cannabis – not associated with the development of dependence.
What receptor does cannabis work on?
Plant cannabinoids such as THC work via the CB1 receptor, mainly exerting effects on the nervous system (brain, adipose, muscle, liver, GI tract, pancreas).
Carbamazepine - what is this?
Anticonvulsant drug - acts on sodium channels
Used in epilepsy -for focal seizures and tonic clonic seizures, NOT ABSENCE SEIZURES
Also used as a mood stabiliser (bipolar disorder), OR for neuropathic pain and trigeminal neuralgia.
Induces liver enzymes.
Carbidopa
Peripherally acting DOPA decarboxylase inhibitor, often combined with Levodopa.
Chlorpromazine (largactil) - what is this?
The first neuroleptic drug - a typical antipsychotic used to treat schizophrenia.
How does chlorpromazine work?
Post-synaptic dopamine receptor ANTAGONIST. Higher affinity for D2 family. Also has high affinity for other neurotransmitter receptors (applies to other antipsychotics too) – e.g. muscarinic Ach, H1, 5-HT2 receptors.
Citalopram - what is it?
SSRI (used for depression)
What are the benefits of citalopram?
No anticholinergic activity, no cardiotoxic effects. Safe in overdose.
What are the adverse effects of citalopram?
The adverse effects are nausea, headaches, GI problems, increased aggression, insomnia, anxiety and sexual dysfunction.
Clozapine - what is this?
Atypical antipsychotic. Blocks D4 receptors with high affinity. Drug of choice in drug resistant schizophrenia. It also has anti-cholinergic effects.
What is the major risk of clozapine?
Agranulocytosis
Cocaine - what is this and how does it work?
Powerful psychostimulant. It inhibits dopamine uptake transporter, but it does not stimulate the release of dopamine directly. This means if nerve cell firing is inhibited, cocaine in ineffective.
What are the effects of cocaine?
Euphoria, increases energy levels, enhances physical performance, suppresses appetite and acts as a local anaesthetic. It potentiates catecholamine activity, causing dilatation of the pupils (mydriasis) and reduces intra-ocular pressure.
Where does cocaine act in the brain?
Nucleus accumbens (euphoria, dependence), hypothalamus (increases temperature and decreases food consumption) and the reticular formation (increases alertness).
Diclofenac
NSAID, COX-1 and COX-2 inhibition. Analgesic and anti-inflammatory.
Disulfiram - what is it used for?
Used in aversion therapies (for alcohol abuse). When it is taken with alcohol it gives an ‘acute hang-over (via acetaldehyde). It blocks acetaldehyde dehydrogenase and so inhibits the metabolism of alcohol, causing the accumulation of acetaldehyde in the blood. This leads to the feeling of sickness.
What is domperidone?
A dopaminergic antagonist which doesn’t cross the BBB, given for the treatment of nausea and vomiting due to L-DOPA.
‘Ecstasy’ (MDMA)
Derivative of amphetamine. It produces its effects primarily by interacting with 5-HT systems (but also modulates dopaminergic and noradrenergic transmission).
Ethosuximide
Anti-epileptic drug that works on T-type calcium channels. It is used in absence seizures.
Fluoxetine
Selective serotonin reuptake inhibitor. Used to treat anxiety and depression.
Fluphenazine
Typical antipsychotic. Can be offered as depot intramuscular injections for slow-release.
Flupenthixol
Typical antipsychotic
Gabapentin
GABA analogue, ion channel modulator. Anti-spastic for MS treatment. Can cause sedation, fatigue and dizziness.
Haloperidol
Typical antipsychotic. Can be offered as depot intramuscular injections for slow-release. Anti-cholinergic effects. Can also be used to treat Huntington’s (anti-dopaminergic). Post-synaptic dopamine receptor ANTAGONIST. Higher affinity for D2 family. Also has high affinity for other neurotransmitter receptors (applies to other antipsychotics too) – e.g. muscarinic Ach, H1, 5-HT2 receptors.
Heroin
Opiate (diacetylmorphine), more potent that morphine. High solubility compared to morphine. Drug of choice in cachexia.
Physical withdrawal symptoms (of all opiates)
Diarrhoea, nausea/vomiting, abdominal cramps, sweating/shivering, hypertension, convulsions, and anxiety.
Ibuprofen
NSAID, COX-1 and COX-2 inhibition. Analgesic and anti-inflammatory.
Imipramine
Tricyclic antidepressant drug. Can be used to treat Huntington’s. NOTE: antidepressant drugs are metabolised by cytochrome P450 enzymes, so if taken with barbiturates (which can induce liver enzymes), the efficacy of the drugs would be decreased due to their metabolism being enhanced.