Retadel

Retadel Uses, Dosage, Side Effects, Food Interaction and all others data.

Retadel is a pharmaceutical of the chelator class. The pharmaceutical form is D-penicillamine, as L-penicillamine is toxic (it inhibits the action of pyridoxine). It is an α-amino acid metabolite of penicillin, although it has no antibiotic properties.

Retadel is a chelating agent used in the treatment of Wilson's disease. It is also used to reduce cystine excretion in cystinuria and to treat patients with severe, active rheumatoid arthritis unresponsive to conventional therapy. Retadel is used as a form of immunosuppression to treat rheumatoid arthritis. Retadel inhibits macrophages, decreases IL-1 and the number of T-lymphocytes, and prevents collagen cross linkage. In Wilson's disease it binds copper, allowing it to be eliminated in the urine.

Retadel
Uses
Dosage
Side Effect
Precautions
Interactions
Uses during Pregnancy
Uses during Breastfeeding
Accute Overdose
Food Interaction
Half Life
Volume of Distribution
Clearance
Interaction With other Medicine
Contradiction
Storage

Trade Name	Retadel
Availability	Prescription only
Generic	Penicillamine
Penicillamine Other Names	(S)-3,3-dimethylcysteine, D-penicillamine, penicilamina, Penicillamine
Related Drugs	Humira, captopril, hydroxychloroquine, Enbrel, Remicade, Rituxan, Orencia, Capoten, zinc acetate, Cuprimine
Type
Formula	C₅H₁₁NO₂S
Weight	Average: 149.211 Monoisotopic: 149.051049291
Protein binding	>80% (bound to plasma proteins)
Groups	Approved
Therapeutic Class
Manufacturer
Available Country
Last Updated:	September 19, 2023 at 7:00 am

Uses

Retadel is a chelator used to treat Wilson's disease, cystinuria, and rheumatoid arthritis.

For treatment of Wilson's disease, cystinuria and active rheumatoid arthritis.

Retadel is also used to associated treatment for these conditions: Poisoning, Lead, Wilson's Disease, Cystine renal calculi, Refractory Rheumatoid arthritis, Severe Rheumatoid arthritis

How Retadel works

Retadel is a chelating agent recommended for the removal of excess copper in patients with Wilson's disease. From in vitro studies which indicate that one atom of copper combines with two molecules of penicillamine. Retadel also reduces excess cystine excretion in cystinuria. This is done, at least in part, by disulfide interchange between penicillamine and cystine, resulting in formation of penicillamine-cysteine disulfide, a substance that is much more soluble than cystine and is excreted readily. Retadel interferes with the formation of cross-links between tropocollagen molecules and cleaves them when newly formed. The mechanism of action of penicillamine in rheumatoid arthritis is unknown although it appears to suppress disease activity. Unlike cytotoxic immunosuppressants, penicillamine markedly lowers IgM rheumatoid factor but produces no significant depression in absolute levels of serum immunoglobulins. Also unlike cytotoxic immunosuppressants which act on both, penicillamine in vitro depresses T-cell activity but not B-cell activity.

Food Interaction

Drink plenty of fluids.
Take on an empty stomach. Co-administration with food decreases bioavailability.

[Moderate] ADJUST DOSING INTERVAL: Food may interfere with the gastrointestinal absorption of penicillamine.

In a study of six healthy volunteers, administration of penicillamine (500 mg) following a standard breakfast reduced the mean peak plasma concentrations of penicillamine by 48% compared to administration in the fasting state.

MANAGEMENT: Retadel should be administered on an empty stomach, at least one hour before or two hours after meals, and at least one hour apart from any other drug, food, or milk.

This permits maximum absorption and reduces the likelihood of inactivation by metal binding in the gastrointestinal tract.

Retadel multivitamins interaction

[Moderate] ADJUST DOSING INTERVAL: Oral administration of aluminum, copper, iron, zinc, magnesium, and possibly other minerals such as calcium may decrease the gastrointestinal absorption of penicillamine, and vice versa.

The proposed mechanism involves chelation of penicillamine to polyvalent cations, which leads to formation of a nonabsorbable complex.

In a study of six healthy volunteers, administration of penicillamine (500 mg) following a single dose of ferrous sulfate (300 mg) or antacid (Maalox Plus 30 mL) reduced the mean peak plasma concentration of penicillamine by 65% and 34%, respectively, compared to administration in the fasting state.

In addition to chelation, some investigators suggest that antacids may also reduce penicillamine bioavailability by increasing gastric pH, which favors the oxidation of penicillamine to its poorly absorbed disulfide form.

These changes could result in diminished therapeutic effects of penicillamine.

Mineral supplements or other products containing polyvalent cations (e.g., antacids or preparations containing antacids such as didanosine buffered tablets or pediatric oral solution) should be administered at least two hours before or two hours after the penicillamine dose.

In addition, pharmacologic response to penicillamine should be monitored more closely whenever these products are added to or withdrawn from therapy, and the penicillamine dosage adjusted as necessary.

When penicillamine is coadministered with Suprep Bowel Prep (magnesium