Interacting drugs -Summary

+ Barbiturate anesthetics

 Narcotics

 barbiturate dose required to induce anesthesia may be reduced Apnea more common with this combination

 Phenotiazines

 preanesthetic use of phenothiazines may raise the frequency and severity of neuromuscular excitation and hypotension in patients who receive barbiturate       anesthesia

Probenecid

 the anesthesia produced by the barbiturate may be extended or acheived at lower doses

 Sulfisoxazole

 sufisoxasole may enhance the anesthetic effects of the barbiturates

General anaesthetic

Respiratory depression, hypersentivity, hypotension,

Flushing, cough, hiccough, heightening of laryngeal refluxes, laryngospasm, hyperglycaemia.

Porphyria.

Special precautions:

Hypovolaemia,uremia, H/O severe asthma, severe cardiac disease, elderly.

Indications:

General anesthetic

Dosage:

Administer IV only. Titrate against patient requirement based on age, sex, and body weight.

Test dose- Inject a small test dose to ascess tolerance or unusual sensitivity.

Anesthesia- Moderately slow induction can be acheived by injection of 50 to 75 mg(2 to 3 ml of 2.5% solution) at intervals of 20 to 40 seconds, depending on patient response.