PAS Pharmacology


About PAS
Amino salicylic acid derivative, Nucleic acid inhibitor, Anti TB antibiotic.
Mechanism of Action of PAS
Para amino salicylic acid is a bacteriostatic drug.PAS
is a structural analogue of Para amino benzoic acid (PABA).PABA binds with Pteridine synthetase for the folic acid synthesis. But PAS has more affinity than PABA for Pteridine synthetase and it inhibits the folic acid synthesis. This will reduce cell multiplication and bacterial growth .PAS also inhibits synthesis of mycobactin which is used for synthesis of cell wall.

Pharmacokinets of PAS
Absorption: It is well absorbed after oral administration. Distribution: It is very widely distributed in the body. Metabolism: It undergoes metabolism in the body.Excretion: It is excreted mainly through urine.
Onset of Action for PAS
1 - 4 hours
Duration of Action for PAS
Half Life of PAS
0.5 - 1 hour
Side Effects of PAS
1. Nausea
2. Vomiting
3. Epigastric pain
4. Anorexia
5. Rash
6. Fever
7. Malaise
8. Hepatitis

Contra-indications of PAS
1. Hypersensitivity to any component of PAS
2. Renal disease
Special Precautions while taking PAS
1. Hepatic dysfunction
2. Gastric ulcers

Pregnancy Related Information
Old Age Related Information
Use with caution
Breast Feeding Related Information
Children Related Information
Indications for PAS
Multi drug resistant Tuberculosis.
Interactions for PAS
Digoxin: Oral absorption of digoxin reduced with subsequent reduction in serum levels of PAS.
Vitamin B12: PAS interferes with Gl absorption of vitamin B12 leading to deficiency. Parenteral vitamin B12 may be required.

Typical Dosage for PAS
Adult: 4 g 3 - 4 times daily
Children: 275 - 420 mg/kg body weight /day

Schedule of PAS
Storage Requirements for PAS
The drug should be stored in refrigerator.
Effects of Missed Dosage of PAS
Take the missed dose as soon as noticed and if it is the time for next dose then skip the missed dose. Continue the regular schedule. Do not double the dose.
Effects of Overdose of PAS
Give supportive measures and symptomatic treatment.

Home Delivery for PAS in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including pas.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for pas and other medicines and health products. Home delivery services for pas may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take pas only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for pas before they complete the sale. You can get this information while placing the order for pas with the pharmacy.

PAS is a generic medicine name and there are several brands available for it. Some of the brands for pas might be better known than pas itself. If the pharmacy that's willing to deliver medicines to your home doesn't have pas in stock, you can ask for one of the branded alternatives for pas.