Drug Name Doxycycline

Inhibition of dihydro-FA reductase (e.g., by methotrexate) depresses the formation of the active species, tetrahydro-FA. Symptoms of deficiency are megaloblastic anemia and mucosal damage. Therapy consists in oral administration of FA or in folinic acid when deficiency is caused by inhibitors of dihydro—FA—reductase. Administration of FA can mask a vitamin B12 deficiency.
Rhinitis. Nasal discharge could be prevented by parasympatholytics; however, other atropine–like effects (pp. 104ff) would have to be accepted. Therefore, parasympatholytics are hardly ever used, although a corresponding action is probably exploited in the case of H1 antihistamines, an ingredient of many cold remedies.

 

Dantrolene interferes with electromechanical coupling in the muscle cell by inhibiting Ca2+ release from the SR. It is used to treat painful muscle spasms attending spinal diseases and skeletal muscle disorders involving excessive release of Ca2+ (malignant hyperthermia).
Some agonists attain a maximal effect even when they occupy only a small fraction of receptors (B, agonist A). Other ligands (agonist B), possessing equal affinity for the receptor but lower activating capacity (lower intrinsic activity), are unable to produce a full maximal response even when all receptors are occupied: lower efficacy. Ligand B is a partial agonist