Must know drugs for Medicine and Pharmacology Practicals

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Insulin

Synthesized by Beta cells of pancreas.
Discovered by Best and Banting.
Administered subcutaneously using Insulin syringe, insulin pens, insulin pumps.

Actions:
1.Insulin facilitates entry of glucose inside the cells.
2.Inhibits hepatic glycogenolysis (so that the blood glucose levels do not rise).
3.Inhibits gluconeogenesis.
4.Promotes protein synthesis and lipogenesis.
5.Causes potassium uptake into the cells.

Uses:
1.Type 1 DM
2.Type 2 DM not responding to oral drugs
3.DKA (Diabetic ketoacidosis)
4.Hyperosmolar hyperglycemic state
5.Gestational DM
6.Hyperkalemia

Side effects:
Hypoglycemia
Allergy
Lipodystrophy (Fat atrophy and hypertrophy at the site of injection)

Contraindications:
Hypoglycemia
Obesity
Allergy to insulin

Insulin analogues
Short acting: (LAG)
L-Lispro
A-Aspart
G-Glulisine

Intermediate acting: Lente and NPH (isophane)

Long acting:
Detemir
Degludec
Glargine

 

Calcium gluconate

Uses
1.Hypocalcemia (1-2 g iv over 2 hours)
2.Hyperkalemia
3.Hydrofluoric acid burns
4.MgSO4 overdose (in pregnancy-eclampsia)

Side effects
Constipation
Nausea
Cardiac arrhythmia
Bradycardia

Contraindications
Kidney stone
High calcium in blood and urine
Ventricular fibrillation

Adrenaline/Epinephrine

Dose: 0.5 ml of 1:1000 solution sc/im

Actions
Adrenaline is a catecholamine secreted by adrenal medulla.
It is a non-selective sympathomimetic.
Alpha -1, 2; Beta-1, 2,3 agonist.

Produces vasoconstriction (by action on Alpha 1) and arrests bleeding.

Produces bronchodilation (by action on Beta 2 receptors).

Uses
Anaphylactic shock
Bronchial asthma
Cardiac resuscitation
Prolongs the Duration on local anesthesia
Controls Epistaxis
Glaucoma

Contraindications
Hypertension
Ischemic heart disease
Congestive cardiac failure
Cardiac arrhythmias

Side effects
Rise in BP
Tachycardia
Palpitations
Tremors
Headache

Hydrocortisone

It is a short acting glucocorticoid.
Rapid onset and short duration of action.

Uses
1.Addison’s disease
2.Anaphylactic shock
3.Status asthmaticus
4.Immunosuppressive (in Rhematoid arthritis, Graft rejection, Gullian Barre syndrome)

Dose in Anaphylactic shock: 200 mg iv

Side effects

1.Cushing’s habitus- Moon face, Buffalo hump, thin limbs
2.Peptic ulcers
3.Hyperglycemia
4.Hypokalemia
5.Sodium retention leading to oedema and rise in BP
6.Weight gain
7.Immunosuppression leading to increased susceptibility to infections
8.Suppression of hypothalamic-pituitary-adrenal axis (rare with short acting steroids like hydrocortisone)

Atropine

Atropine is an anticholinergic agent.
It acts by blocking the muscarinic receptors.
There is loss of light reflex and loss of accommodation with atropine use.

Uses
1.Organophosphorous poisoning
2mg iv stat, should be repeated every 5-10 mins doubling the dose, till signs of atropinisation occur.

2.Mushroom poisoning
3.Curare poisoning (along with neostigmine, to counteract the muscarinic side effects of neostigmine)
4.For fundoscopic examination as a mydriatic
5.Used in sialorrhea or hypersalivation

Side effects
1.Dryness of mouth
2.Urinary retention
3.may precipitate acute congestive glaucoma.
4.Atropine poisoning (Belladonna poisoning) symptoms include:
Hot as a hare-Increase in body temperature
Red as a beetroot- Red and flushed skin due to cutaneous vasodilation
Dry as a bone-Due to reduced secretions
Blind as a bat-Blurring of vision, Photophobia
Mad as a hatter– Restlessness, hallucinations

 

Pralidoxime

It is a cholinesterase reactivator.

Uses
Organophosphorous poisoning
2gm iv slowly
(effective in the first 48 hours)

Contraindications
Reduced kidney function
Enlarged prostate

Side effects
Local irritation
Tachycardia
Hypotension

Neostigmine

Neostigmine is an anticholinesterase.
It inhibits cholinesterase and increases the action of acetylcholine at the NMJ.

Dose: 15-30 mg oral
2 mg im

Uses:
1.Alzheimer’s disease
2.Atropine poisoning
3.Curare poisoning
4.Myasthenia gravis (improves muscle power)
5.Paralytic ileus
6.Postoperative urinary retention
7.To reverse pupillary dilatation after refraction testing (miotic)

Side effects
Muscarinic side effects- increased sweating, salivation, vomiting, diarrhoea

Nicotinic side effects- Tremors, fasciculations

Neostigmine does not cross the Blood Brain barrier and hence does not cause any central side effects.

 

 

Furosemide

Furosemide is a loop diuretic.
Site of action is the thick ascending limb of the Loop of Henle.
It blocks the Na+ K+ 2Cl- cotransporter.

Loop diuretics are high ceiling diuretics as they are highly effective (have maximum sodium excreting capacity as compared to other diuretics).

Rapid onset and short duration of action.

Uses
Renal edema
Cardiac edema
Hepatic edema
Cerebral edema
Acute pulmonary edema
Mild hyperkalemia and hypercalcemia

Side effects
Hyponatremia
Hypokalemia
Hypocalcemia
Hyopomagnesaemia
Hyperglycemia
Hyperlipidemia
Hyperuricemia
Ototoxicity (deafness, tinnitus, vertigo)
Hypersensitivity

Sodium bicarbonate

Sodium bicarbonate combines with Hydrochloric acid in the stomach to form sodium chloride, water and carbon dioxide.
It is a systemic antacid.

Uses
1.Metabolic acidosis.
2.To render urine alkaline in Urinary tract infection.
3.To prevent precipitation of uric acid.

Contraindications
1.Renal failure
2.Hypertension
3.Edema
4.Congestive cardiac failure

Side effects
1.Systemic alkalosis
2.Retention of sodium
3.Perforation in patients with gastric ulcer because of distension caused by release of carbon dioxide

Streptokinase

It is a thrombolytic agent derived from Beta-hemolytic streptococci.

Mechanism: Streptokinase converts plasminogen to plasmin. Plasmin degrades fibrin into fibrin degradation products and hence it dissolves the blood clot rapidly.

Uses
1.Acute Myocardial infarction
2.Deep vein thrombosis
3.Pulmonary embolism
4.Acute ischemic stroke

Dose: 1.5 million units iv as an infusion over 1 hour.

Contraindications
1.Active bleeding (except menses)
2.Severe uncontrolled hypertension
3.History of hemorrhagic stroke
4.Ischemic stroke in the last 3 months
5.Suspected aortic dissection
6.Known intracranial neoplasm, aneurysm or arteriovenous malformation

Side effects
1.Bleeding
2.Hemorrhagic stroke
3.Hypotension
4.Anaphylaxis

Unfractionated Heparin

Dose: 10,000 units iv

Action
1.Heparin strengthens the action of antithrombin III by forming a complex with it which inhibits the activated clotting factors like IIa, IXa, Xa, XIa, XIIa and XIIIa by forming a complex with them.

2.At low concentration, heparin inhibits the conversion of prothrombin to thrombin.

3.At high concentration, heparin has an antiplatelet action.

4.Heparin reduces blood lipid levels by releasing lipoprotein lipase from vessel wall and tissues.

Uses
1.Acute Myocardial infarction
2.Deep vein thrombosis
3.Transient ischemic attack
4.Ischemic stroke

Contraindications
Hemophiliacs
Hypertension (severe)
intracranial Hemorrhage
Heparin induced thrombocytopenia
Renal failure

Side effects
Bleeding
Heparin induced thrombocytopenia (HIT)
Hypersensitivity
Osteoporosis
Reversible alopecia

Heparin has a narrow therapeutic range and hence requires aPTT monitoring.
Bleeding is the most common side effect.
Heparin overdose is treated with protamine sulphate (heparin antagonist).

Low molecular weight Heparins

They are administered subcutaneously.

Action: Low molecular weight Heparins produce anticoagulant effect mainly by inhibition of factor Xa through antithrombin.

Examples: Dalteparin, Enoxaparin

Uses, side effects and contraindications are same as unfractionated heparin.

Advantages:
1.Have a higher bioavailability than unfractionated heparin.

2.Have a longer duration of action.

3.They do not require routine aPTT monitoring.

4.Have a lower incidence of thrombocytopenia (HIT) and osteoporosis.

 

 

Salbutamol

Beta-2 agonist, it is short acting (rapid onset and short duration of acting).

Action:
1.Bronchodilation
2.Relaxation of pregnant uterus
3.Promote uptake of potassium into the cells
4.Promote glycogenolysis
5.They cause tremors

Uses:
1.Bronchial asthma and Chronic obstructive pulmonary disease (COPD): It is administered using a metered dose inhaler in the form of aerosol. Dose is 100-200 microgram every 6 hours or as needed.
2.Used in premature labour to delay the onset of labour
3.Hyperkalemia

Side effects
Tremor
Tachycardia
Hyperglycemia
Hypokalemia

Short acting beta-2 agonists: Salbutamol, Terbutaline

Long acting beta-2 agonists: Salmeterol, Formoterol

 

 

Amiodarone

It is a class III antiarrhythmic drug.

Action:
Blocks potassium channels
Blocks sodium channels
Blocks calcium channels
Blocks Beta adrenergic receptors

Hence, it has a wide spectrum of action.

Dose:
150 mg iv over 10 mins, then
1mg/min for 6 hours, then
0.5 mg/min for next 12 hours

Uses
1.Used to slow down the ventricular rate and restore normal sinus rhythm in Atrial fibrillation
2.Used to prevent recurrent Ventricular tachycardia

Side effects: (4H, 4P)
Hypotension
Hypothyroidism
Hyperthyroidism
Hepatotoxic
Peripheral neuropathy
Pulmonary fibrosis
Pigmentation of skin
Photosensitivity

Amiodarone is the longest acting antiarrhythmic drug.
Amiodarone has a low incidence of torsades de pointes.

 

Digitalis/Digoxin

Dose: 0.25 mg/ml iv till digitalisation occurs.

Actions
1.Positive inotropic effect- increases the force of contraction of the heart
2.Negative chronotropic effect- decreases the heart rate
3.Reduces AV nodal conduction and Purkinje fibre conduction

Uses
1.Congestive cardiac failure (CCF)
2.Atrial fibrillation
3.Atrial flutter
4.Paroxysmal supraventricular tachycardia (PSVT)

Side effects
Digoxin has a narrow margin of safety.

1.Arrhythmias like Ventricular premature beats, ventricular tachycardia, pulsus bigeminy
2.Gynaecomastia
3.Nausea, vomiting
4.Headache, confusion, disorientation
5.Hallucinations

 

Dobutamine

It is a synthetic catecholamine.

Action
Acts on Beta 1, Beta 2, Alpha 1 receptors.
Inotropic effect
Increase cardiac output

Uses
Acute heart failure
Cardiogenic shock

Side effects
Tachycardia
Rise in blood pressure
Development of tolerance

Verapamil

It is a calcium channel blocker belonging to class phenylalkylamine.

Action:
1.Negative inotropic effect (decreases force of contraction)
2.Negative chronotropic effect (decreases heart rate)
3.Negative dromotropic effect (depresses SA node and slows down AV node conduction)

Uses
1.Stable angina (Exertional angina)
2.Hypertension
3.Hypertrophic cardiomyopathy
4.Supraventricular arrhythmia
5.Prophylaxis of migraine

Side effects
Sinus bradycardia
May precipitate CCF
Oedema
Constipation

 

Nifidepine

It is a calcium channel blocker belonging to class dihydropyridine.

Action:
It is a potent arterial dilator and reduces peripheral vascular resistance.

Uses:
1.Stable angina
2.Variant angina (it is angina due to coronary vasospasm)
3.Prevention and treatment of cerebral vasospasm
4.Raynaud’s phenomenon
5.Used as a uterine relaxant in premature labour
6.Hypertension

Side effects
Postural hypotension
Reflex tachycardia
Palpitations
Oedema

Diltiazem

It is a calcium channel blocker belonging to class benzothiazepine.

Action:
It has actions of both verapamil and nifidepine.

Uses
Hypertension
Stable angina
Variant angina

Side effects
Hypotension
Bradycardia
Oedema
Headache

Phenytoin sodium

Action
•Delays recovery of sodium channels from the inactivated state.
•At high concentration, phenytoin inhibits calcium influx into the neuron, reduces glutamate levels and increases response to GABA (GABA is an inhibitory neurotransmitter).

Hence, phenytoin stabilizes the neuronal membrane.

Dose: 200-400 mg

Uses
1.Generalized tonic clonic seizures
2.Simple partial seizures
3.Complex partial seizures
4.Status epilepticus
5.Trigeminal neuralgia (2nd choice of drug)

Side effects (note the H’s)
1.Hypertrophy and Hyperplasia of gums
2.Hirsutism
3.Hyperglycemia (reduced insulin secretion)
4.Hypocalcemia
5.Hypersensitivity reactions
6.Hepatic necrosis
7.Fetal Hydantoin syndrome (cleft lip, cleft palate, digital hypoplasia, etc due to teratogenic effect)
8.Osteomalacia
9.Megaloblastic anemia
10.Nystagmus, vertigo, ataxia
11.Cardiac arrhythmia (on iv use)

Labetalol

Alpha(1) + Beta (1 and 2) blocker

Dose:200-1000 mg

Uses
1.Essential hypertension
2.Hypertensive emergencies
3.Thyrotoxic crisis
4.Anxiety neurosis
5.Open angle glaucoma

Side effects
1.Postural hypotension
2.Hypoglycemia (therefore they should be used with caution in diabetics, also they mask the symptoms of hypoglycemia)
3.Bronchospasm
4.Hepatotoxicity

 

Oseltamivir

Action: It inhibits neuraminidase enzyme and hence interferes with the release of progeny virions from infected cells.

Route: oral

Dose:
For prophylaxis– 75 mg OD for 7 days
For treatment– 75 mg BD for 5 days

Uses
Influenza A
Swine flu (H1N1)
Bird flu (H5N1)
Influenza B

Side effects
Nausea
Vomiting
Abdominal discomfort

Artesunate

Dose
2mg/kg iv/im stat, repeat at 12 hours and 24 hours.
Then give once a day till the patient is able to take oral medication.
Oral dose : 100 mg BD for 3 days

Action
Artesunate causes damage to the proteins of the parasite and also causes lipid peroxidation, leading to the death of the parasite.

Uses
1.Treatment of chloroquine resistant plasmodium falciparum malaria infection.
2.Treatment of severe or complicated Plasmodium falciparum malaria infection (cerebral malaria).

Side effects
Prolongation of QT interval
Mild gastrointestinal disturbances
Neutropenia
Reticulocytopenia

Rifampicin

Dose: 450-600 mg/day orally

Uses
1.Tuberculosis
2.Leprosy
3.Meningitis(prophylaxis of Hemophilus influenzae and meningocoocal meningitis)
4.Atypical mycobacterial pneumonia
5.Brucellosis
6.Diphtheria

Side effects (4R)
1.Redness and watering of eyes.
2.Orange Red urine and secretions.
3.Renal failure and shock (nephrotoxic)
4.Respiratory syndrome (breathlessness and shock)

Dopamine

It is a catecholamine.

Action

At low dose (<2mcg/kg/min), it acts on D1 receptors. This dilates renal, mesenteric and coronary blood vessels and hence, increased GFR and urine output.

At moderate dose (2-5 mcg/kg/min), it acts on Beta-1 receptors of the heart and hence, increases myocardial contractility and cardiac output.

At high dose (>10 mcg/kg/min), it acts on Alpha-1 receptors which cause generalized vasoconstriction. This causes reduced blood flow to renal, mesenteric and other organs. Therefore, at high doses, dopamine is not beneficial to the body.

Uses
1.Cardiogenic shock
2.Septic shock
3.Severe heart failure with renal impairment

Side effects are due to sympathetic stimulation.
1.Hypertension
2.Tachycardia
3.Cardiac arrhythmias
4.Angina