Rebound phenomenon

Postural hypotension, first-dose effect, and rebound phenomenon are not commonly seen. 

The rebound phenomenon is plaiirly a potential hazard and the use of a p-adrenoceptor blocker in the presence of ischaemic heart disease would be safer if rebound could be eliminated, p-adrenoceptor blockers that are not pure antagonists but have some agonist (sympathomimetic ischaemic) activity, i.e. partial agonists, may prevent the generation of additional adrenoceptors (up-regulation). Indeed there is evidence that rebound is less or is absent with pindolol, a partial agonist P-adrenoceptor blocker. 

Miller RR, Olson HG, Amsterdam EA, Mason DT. Propranolol-withdrawal rebound phenomenon. Exacerbation of coronary events after abrupt cessation of antianginal therapy. N Engl J Med 1975 293(9) 416-18. 

Peritoneal dialysis clears only 9-15 mL/min of lithium, and is therefore not recommended for the treatment of acute lithium toxicity [125,126]. Conventional hemodialysis, on the other hand, decreases serum lithium levels at a rate of 1 mEq/L with every 4 hours of treatment [126]. Several treatment sessions of hemodialysis may be required, and serum lithium levels need to be checked frequently even after hemodialysis, because of the shifting of hthium from inside the cells (lithium rebound phenomenon). In those patients who may have ingested the sustained-release form of lithium, continued absorption from the GI tract may cause a rise in serum hthium levels between hemodialysis sessions [128]. 

In 12 hours, all elements had returned to a level above the pretreatment level, particularly the white cells. This Immune Rebound Phenomenon, a phrase coined by Dr. Farr, indicates a strong stimulation of the immune (defense) system. This helps explain why the H202 treatments are effective in all types of infectious diseases, i.e., influenza, allergies, Candida, Ebstein-Barr, CMV, herpes, etc. Dr. Farr and his group are currently studying the effects of H202 in AIDS, hepatitis, encephalitis, and other serious viral diseases. Repeated infusions, as often as... 

Figure 19.5 shows the fitting results for PEPCK mRNA (B), PEPCK activity (C), and cAMP (D) in rat liver after a single injection of methylprednisolone. The acute tolerance/rebound phenomenon in PEPCK mRNA was nicely described by the dual action of CS on both gene transcription and degradation. 

Nitroprusside has a rapid onset of action and a duration of action of less than 10 minutes, necessitating its administration by continuous intravenous infusion. This allows for precise dose titration based on measured clinical and hemodynamic parameters. It, like other vasodilators used in heart failure, should be initiated at a low dose (0.1 to 0.2 mcg/kg per minute) to avoid excessive hypotension and then increased by small increments (0.1 to 0.2 mcg/kg per minute) every 5 to 10 minutes as needed and tolerated. Usually effective doses range from 0.5 to 3 mcg/kg per minute. A rebound phenomenon has been reported after abrupt withdrawal of nitroprusside in patients with heart failure and is apparently due to reflex neurohormonal... 

Sinzinger, H., Silberbauer, K., Horsch, A.K. and Gall, A. (1981). Decreased sensitivity of human platelets to PGI during long-term intraarterial prostacyclin infusion in patients with peripheral vascular disease - a rebound phenomenon Prostaglandins, 21, 49-51... 

A bone subcompartment accessible to chelants is evident in the adult data of Araki and Ushio (1982), where the extent of plumburesis in human subjects rises with age, an observation consistent with bone Pb increases with age but not the relatively stable soft tissue Pb levels over various age intervals of adulthood. In addition, the likelihood of chelants mobilizing Pb from high stores of Pb can also be seen in the rebound phenomenon using these agents, where an initial significant decline in PbB and increased plumburesis is followed by a rise in PbB owing to re-equilibrating Pb compartments (Chisolm and Barltrop, 1979 Chisolm et al., 1985). 

A remaining issue with use of the traditional as well as the newer, outpatient chelants is the rebound phenomenon. Some insight about rebound biokinetics may be found in the Cory-Slechta et al. (1987) report discussed above and other citations there. They noted that alternate administrations across a serial dosing protocol, i.e., injections 1 and 3, produced bone Pb reductions but injections 2, 4, and 5 did not. They postulated return of mobilized Pb back to bone stores. If such redeposited Pb is more mobile than initially unmobilized Pb, this fraction s biokinetics of Pb movement to blood may differ from overall bone Pb mobility. 

Franks MA, Macritchie KA, Mahmood T, Young AH. Bouncing back is the bipolar rebound phenomenon peculiar to lithium A retrospective naturahstic study. J Psychopharmacol 2008 22(4) 452-6. 

Immune reconstitution inflammatory syndrome is a reported rebound phenomenon after withdrawal of natalizumab [252, 253 ]. 

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