Finasteride

5-alpha reductase inhibitor

Orally active
used in BPH
Dose 5 mg/day
Decrease prostate volume
Decrease symptom score
Decrease DHT level in prostate
Also used for androgenic alopecia
ADR: loss of libido & impotense in 5 % patients

Adverse effects of corticosteroids

Iatrogenic Cushing’s syndrome
Hyperglycaemia, glycosuria, diabetes
Myopathy (negative nitrogen balance)
Osteoporosis (vertebral compression fracture)
Retardation of growth (children)
Hypertension, oedema,CCF
Avascular necrosis of femur
HPA axis suppression
Behavioral toxicity: Euphoria, psychomotor reactions, suicidal tendency
Ocular toxicity: steroid induced glaucoma,posterior subcapsular cataract.
Others:
Superinfections
Delayed wound healing
Steroid arthropathy
Peptic ulcer
Live vaccines are dangerous
By Dr. Ahmad Najmi, Index Medical College, Indore

Contraindications of corticosteroids

Infections
Hypertension with CCF
Psychosis
Peptic ulcer
Diabetes mellitus
Osteoporosis
Glaucoma
Pregnancy : (prednisolone preferred)

Therapeutic uses of corticosteroids

(By Dr. Ahmad Najmi, Index Medical College, Indore)

1. Endocrine Disorders
Acute adrenal insufficiency
Primary adrenocortical insufficiency
Ad. Insufficiency second. to Ant. Pituitary
Congenital adrenal hyperplasia
2. Rheumatic carditis
Not responding to salicylates
Severely ill pts.
Prednisolone 40mg in divided doses
Salicylates given concurrently to prevent reactivation
3. Arthritis
Not the drug of first choice
Prednisolone 5 or 7.5 mg
Intra-articular injection
4. Renal diseases (Nephrotic syndrome)
Prednisolone 60 mg in divided doses for 3 – 4 weeks
If remission occurs continue for 1 year
Do not modify the course of disease; Some may benefit
5. Collagen diseases
DLE, pemphigus vulgaris, polyarteritis nodosa
Defect in connective tissue proteins in joints, various organs and deeper layer of skin
6. Allergic diseases
Anaphylactic shock, blood transfusion reaction, hay fever
Prednisolone (short course)
7. Bronchial asthma
Not routinely used except in Status asthmaticus
Methyl prednisolone sodium i.v. given followed by oral prednisolone
Inhaled steroids (Minimal HPA axis suppression
8. Ocular diseases
Outer eye & anterior segment: local application
Posterior segment: systemic use
Caution: bacterial, viral & fungal conjunctivitis
9. Dermatological conditions
Pempigus: Life saving therapy is steroids
Eczema, dermatitis & psoriasis: respond well
10. . Diseases of intestinal Tract
Ulcerative colitis: cortisol retention enema
11. Cerebral oedema
Questionable value in cerebral oedema following trauma, cerebrovascular oedema
Valuable in oedema associated with neoplasm and parasites
13. Malignancy
Part of multi drug regimens for acute lymphatic leukaemia (children), chronic lymphatic leukaemia (adult)

Prednisolone 1mg/Kg start; gradually reduce the dose

Guidelines for topical steroids

Penetration differs at different sites:
High: axilla, groin, face, scalp, scrotum
Medium: limbs, trunk
Low: palm, sole, elbow, knee
Occlusive dressing enhance absorption (10 fold)
Absorption is greater in infants & Children
Absorption depends on nature of lesion:
High: atopic & exfoliative dermatitis
Low: hyperkeratinized & plaque forming lesions
More than 3 applications a day is not needed
Choice of vehicle is important
Lotions & creams: for exudative lesions
Sprays & gels: for hairy regions
Ointments: for chronic scaly lesions
(By Dr. Ahmad Najmi, Index Medical College, Indore)

OSTEOPOROSIS

Osteoporosis is a serious public health issue. The past 10 years have seen great advances in our understanding of its epidemiology, pathophysiology, and treatment, and further advances are rapidly being made. Clinical assessment will probably evolve from decisions mainly being made on the basis of bone densitometry, to use of algorithms of absolute fracture risk. Biochemical markers of bone turnover are also likely to become more widely used. Bisphosphonates will probably remain the mainstay of therapy, but improved understanding of the optimum amount of remodelling suppression and duration of therapy will be important. At the same time, other diagnostic and therapeutic approaches, including biological agents, are likely to become more widespread. Strontium ranelate is a fairly new antiosteoporotic agent that has been approved in the European Union for thetreatment of postmenopausal osteoporosis. Although postulated to increase bone formation while reducing bone resorption, its mechanism of action remains unclear.

Mechanism of action of antiepileptic drugs

enhancement of GABA action
inhibition of sodium channel function
inhibition of calcium channel function
Newer drugs act by other mechanisms, yet to be elucidated.
Drugs that block glutamate receptors are effective in animal models but are not yet developred for clinical use.
Tonic clonic seizures:
carbamazepine (preferred because of low incidence of side-effects), phenytoin, valproate
use of a single drug is preferred when possible to avoid pharmacokinetic interactions
newer agents (not yet fully assessed) include vigabatrin, lamotrigine, felbamate, gabapentin.
Partial (focal) seizures: carbamazepine, valproate; clonazepam or phenytoin are alternatives.
Absence seizures (petit mal): ethosuximide or valproate
valproate is used when absence seizures coexist with tonic-clonic seizures, since most other drugs used for tonic-clonic seizures can worsen absence seizures.
Myoclonic seizures: diazepam intravenously or (in absence of accessible veins) rectally.
Neuropathic pain, e.g. carbamazepine, gabapentin (see Ch. 40).
To stabilise mood (as an alternative to lithium), e.g. carbamazepine, valproate

Valproate:
chemically unrelated to other antiepileptic drugs
mechanism of action not clear; weak inhibition of GABA transaminase; some effect on sodium channels
related few unwanted effects: baldness, teratogenicity, liver damage (rare, but serious).
Phenytoin:
acts mainly by use-dependent block of sodium channels
effective in many forms of epilepsy, but not absence seizures
metabolism shows saturation kinetics; therefore, plasma concentration can vary widely and monitoring is needed
drug interactions are common
main unwanted effects are confusion, gum hyperplasia, skin rashes, anaemia, teratogenesis
widely used in treatment of epilepsy; also used as antidysrhythmic agent

Carbamazepine:
derivative of tricyclic antidepressants
similar profile of that of phenytoin, but with fewer unwanted effects
effective in most forms of epilepsy (except absence seizures); particularly effective in psychomotor epilepsy; also useful in trigenimal neuralgia
strong enzyme-inducing agent; therefore, many drug interactions
low incidence of unwanted effects; principally sedation, ataxia, mental disturbances, water retention.

Other drugs include:
phenobarbital: highly sedative
various benzodiazepines (e.g. clonazepam); diazepam used in treating status epilepticus.