Hey folks so I took 2 extra strength tums about 1 hour ago and I wanna know if i can safely take 20mg xr adderall?? I have a small tolerance to adderall but nothing much. I figured 20mg would be pretty safe but I wanna be sure thank u!!

it might make you 20mg dose feel more like 26mg. That's about it.
Interactions with Dietary Supplements
Magnesium
Dextroamphetamine can increase blood levels of magnesium, which causes significant lowering of the calcium to magnesium ratio in the blood. The change in this ratio may in part explain the effectiveness of stimulants like dextroamphetamine in hyperactive boys.1 Another magnesium-amphetamine interaction involves supplements of magnesium hydroxide, which are known to cause retention of amphetamines in the body.2 This could theoretically result in increased blood levels of these drugs. Finally, animal studies have suggested that magnesium supplements can increase learning and enhance the behavioral response to stimulants.3 For these reasons, the use of magnesium along with amphetamines may enhance the effectiveness of these drugs in the treatment of ADD, but controlled studies of this possibility are needed.
Vitamin C
Ingestion of some types of vitamin C results in acidification of the intestinal contents and thus a decreased absorption of amphetamines.4 Supplements containing vitamin C should be taken an hour before or two hours after taking amphetamines.
Tyrosine
Tyrosine is an amino acid used by the body to produce brain chemicals stimulated by amphetamines. Reduced stimulant effects of amphetamines were observed in individuals who had been made tyrosine deficient.5 It is possible that a dietary deficiency of tyrosine may reduce the effectiveness of amphetamines. Tyrosine deficiency is not common unless a protein deficiency exists. Adequate tyrosine intake from dietary protein or supplements is necessary in individuals taking amphetamines.
Lithium
Lithium is a mineral that may be present in some supplements and is also used in large amounts to treat mood disorders such as bipolar disorder (manic depression). Taking lithium at the same time as amphetamines may inhibit the appetite suppressant and stimulatory effects of the amphetamines.6 Therefore, people taking amphetamines should take lithium only under the supervision of a doctor.
Vitamin B6
Occasionally, individuals taking amphetamines develop compulsive behavior and anxiety, even after the drug is discontinued. When this side effect occurred in an eight-year-old boy,7 supplementation with 200 mg vitamin B6 each day for one week followed by 100 mg daily, reduced the compulsive behavior and anxiety within three weeks. The symptoms were eliminated after a few months of treatment. Controlled research is needed to determine conclusively the usefulness of vitamin B6 supplementation for preventing and treating this side effect.
L-tryptophan
In an uncontrolled study of schizophrenic patients, 200 mg per day of L-tryptophan reduced disturbances in thinking, as well as hallucinations caused by dextroamphetamine.8 Symptoms of psychosis rarely occur in people who take amphetamines and are not schizophrenic. Controlled research is needed to establish the benefits of L-tryptophan and related supplements for people taking amphetamines.
Interactions with Herbs
Ephedra
Ephedra sinica contains a compound called ephedrine. A seven-year-old boy who had 12 mg of ephedrine twice daily added to his dextroamphetamine therapy experienced improvement in hyperactive behavior.9 He also experienced relief from symptoms, such as headaches and spots before his eyes, that may have been caused by dextroamphetamine. However, concurrent use of amphetamines with other stimulants such as ephedrine or Ephedra sinica could cause excessive stimulation of the heart or nervous system. For this reason, such combinations should be used with great caution, and only under the supervision of a doctor.
Veratrum (Veratrum sp.)
Veratrum (Hellebore) is an herb used by doctors of natural medicine to treat high blood pressure;however, amphetamines can inhibit this effect.10 Therefore, people taking veratrum to treat hypertension should avoid amphetamines.
Interactions with Foods and Other Compounds
Fruit juices
Fruit juices may acidify the intestinal contents, causing reduced absorption of amphetamines.11 Therefore, juices should be consumed an hour before or two hours after administration of amphetamines.
Alcohol
The combination of alcohol and methamphetamine makes the heart work harder and consume more oxygen, which may produce unwanted effects.12 Alcohol consumption may also suppress the breakdown of amphetamines, causing elevations in blood levels of the drug.13 Individuals taking amphetamines should avoid alcoholic beverages, especially if they have known heart problems.