Tricylic Compounds include-
      Tertiary amines - Amitriptyline,Clomipramine,Doxepin,Imipramine,Trimipramine
      Secondary amines - Amoxapine, Desipiramine, Nortriptyline,Portriptyline
      Refer - Amitriptyline

 Tetracyclines Compounds include -  Maprotiline, Mitrazapine, Mianserin
        
Triazolopyridine  group  - Trazadone
    
 Aminoketone  group -- Bupropion
        
Phenypiperazine group - Nefazodone  
   
Phenethylamine  group  - Venlafaxine
   
Interacting drugs - Summary

+ TCA

Cimetidine 
 TCAs serum conc.increased resulting in eg. dry mouth,urinary retention, blured vision
                         
Clonidine
 dangerous elevation of blood pressure and hypertensive crisisoccured. Avoid
  Avoid coadministration of TCA

Dicumarol-
TCAs may increase the half-life or bioavailability of dicumarol
                         
Disulfram-
TCAs coadministration result in acute organic brain syndrome.
                     
Fluoxetine-
may increase the pharmacologic and toxic effects of TCAs 
                     
Guanethidine-
TCAs  antogonise antihypertensive action by inhibiting intake into adrenergic
 neurons. Avoid combinations when possible
                      
Haloperidol-
may increase serum conc. of TCAs , tonic =clonic seizure occured in one patient 

Levodopa-
absorption may be delayed and its bioavailibility decreased by TCAs. 
                       
MAOIs- 
 should not be given with  or immediately following TCAs .                  
                    
Oral contracep- 
 Estrogen may increase or decrease the pharmacologic effect of TCAs                                    

Phenothiazines -
 may increase serum TCA by inhibting hepatic metabolism

Smoking -
 may increase the metabolic biotransformation of TCAs

Relief and symptoms of depression

Tricylic Compounds include- Tertiary amines - Amitriptyline,Clomipramine,Doxepin,Imipramine,Trimipramine

Secondary amines - Amoxipine, Desipramine, Nortriptyline,Portriptyline

Refer - Amitriptyline

Tetracyclines Compounds include - Maprotiline, Mitrazapine, Mianserin

Triazolopyridine group - Trazadone

Aminoketone group -- Bupropion

Phenypiperazine group - Nefazodone

Phenethylamine group - Venlafaxine

Ventricular fibrillation in patients with preexisting cardiac d iseases.

Agranulocytosis. Thrombotopenia.

Postural hypotens,tachycardia,

Cardiac arrhythmias,conduction disturbances.

Drymouth,blurring of vision,constipation,

Urinary retension, fatigue, dizziness,

Weakness,tremors, headache,

Confusion and delirium in elderly,

Weight gain, sexual disturbances.

Hypersenitivity,acute recovery follwing MI,

Concomittant therapy with MAOIs or within 14 days of discontinuing them.

Narrow angle glaucoma,

Pregnancy,

Heart block,

Severe liver disease.

Special precautions:

Recovery after MI,

Lactation, Pregnancy,

Elderly,

CVS disease Lliver impairment,

Epilepsy, psychosis,

Avoid alcohol.

New drugs approved For Marketing by Drug Controller General of India(DCGI )                          during the period January 1988 to November 2014                                                                     (Ref- IDMA Annual Publication 2015)

Indications:

Relief and symptoms of depression

Dosage:

75mg/day in divided doses. .May increase to 150mg/day. Make increases in afternoon or at bed time alternately.

Alternately, Initiate therapy with 50 to 100mg at bed time. Increase by 25 to 50mg as necessary, to a total of 150mg/day.

For Availability/supplies 

EVIDENCE BASED MEDICINE (MIMS April 2003)

Post-herpetic Neuralgia.

Comparitive effectiveness of various interventions

Prevention of post-herpetic neuralgia

Beneficial

1. Oral antiviral agents such as acyclovir, famciclovir, valaciclovir, netivudine

2. Tricyclic antidepressants (amitriptyline)

Unknown effectiveness

1. Levodopa

2. Amantadine

3. Isoprinosine

4. Adenosine monophosphate

Unlikely to be beneficial

1. Topical antiviral agents (idoxurine) for relief of acute oain only

2. Cimetidine

Effective or harmful

1. Corticosteroids

Relieving established post-herpetic neuralgia

Beneficial

1. Tricyclic antidepressants (amitriptyline)

2. Oxycodone (opiod)

3. Gabapentin (anticonvulasant)

Unknown effectiveness

1. Capsaicin (topical counterirritant)

2. Topical lignocaine

Ineffective or harmful

1. Epidural morphine

2. Dextromethorphan

KEY POINTS

1. Daily acyclovir reduced the relative risk of of post-herpetic pain at six months by about 50 % compared with placebo

2. Famciclovir significantly reduced pain duration after acute herpes zoster

 3. Idoxuridine was associated with short term pain relief in acute herpes zoster but did not prevent post-herpetic neuralgia

4. Conflicting evidence on whether corticosteroids alone prevent post-herpetic neuralgia. Limited evidence that high dose steroids and antiviral agents combined may speed healing of acute zoster. No evidence that it reduces post-herpetic neuralgia

5. Amitriptyline started during the acute episode reduced prevalence of post-herpetic neuralgia at six months.

6. Insufficient evidence on the effect of other drug treatment.

1. Do not discontinue therapy or take other drugs without the consent of physician. Abrupt discontinuation of therapy may cause nausea,headache and malaise.

2. May cause drowsiness or blurred vision. Use caution while driving or performing other tasks which require alertness.

3. Avoid taking alcohol or other CNS depressant drugs

4. Avoid prolonged exposure to sunlight or sunlamps; photosensitivity may occur.

5. Allergies

Tell your doctor if you have ever had any unusual allergic reaction to any tricyclic antidepressant to carbamazepine, maprotiline or trazadone. Also tell to your if you are allergic to any substances such as foods, preservatives or dyes.

6. Pregnancy

Studies in animals have shown that some tricyclic antidepressants may cause unwanted effects in the fetus.

7. Breast feeding

Tricyclic antidepresants pass into breast milk. Doxepin have been reported to cause drowsiness in the nursing babies.

8. Children

Children are specially sensitive to the effects of this medicine. Side effects in children taking this medicine for bedwetting usually disappears on continued use. Other most common side effects are nervousness, sleeping problems, tiredness, and mild stomach upset. Check with your doctor if these side effects continue to persist.

9. Elderly

Drowsiness, dizziness, confusion, vision problems, dryness of mouth, constipation, and problems in urinating are more likely to occur in elderely patients.

10. Other medicines

If you taking tricyclic antidepressants, it is necesary for your doctor to know if you are taking any other medicines- Amphetamine or Appetite suppressants or Ephedrine or ephinephrine or Isoproterenol or Medicine for asthma or for colds , sinus problems, or hay fever or other allergies or Phenylephrine- use of these medicines with tricyclic may increase the risk of serious side effects on the heart

11. Other medical problems

Tell your doctor ifyou have any other medical problems- Alcohol abuse- drinking alcohol may cause increased CNS depresant efects. Asthma or Biploar disorder or Blood disorders or Convulsions or Difficult urination or Enlarged prostrate or Glaucoma or increased eye pressure or Heart disease or High blood pressure ir Schiophrenia - tricyclic antidepressants may make the conditiond worse

 12. Missed dose

if you miss a dose and dosing is Once a day at bed time- do not take mised dose in the morning since it may cause disturbing side effects during waking hours. check with your doctor More than one dose a day- take the mised dose as soon as possible. However if it is almost time for the next dose , skip the missedcdose and go back to your regular schedule. Do not double doses.

13. Storage

Keep out of reach of children. Overdose of this medicine is too dangerous for children. Store away from heat and direct light. Do not store the tablet or capsule form of this medicine in the bathroom,near the kitchen sink or in other damp places Keep the liquid formof this medicine from freezing Do not keep outdated medicines. Be sure that discarded medicine is out of reach of children

14. Food

Take with or without food

15. AVOID CONCURRENT USE WITH ERYTHROMYCIN

Take with or without food

Pregnancy:

Safety for use during pregnancy not been established,use only when clearly indicated.

Lactation:

The drug is excreted into breast milk in low concentrations. Excercise caution while using in nursing women.